PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
PRESTO 3.2
T
A
I
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Version 1.0
May 1999
The contents of this ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
PRESTO History
1988 Development starting
1990 SPRINT & SIGHTS High ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
PRESTO flow
Extract data
Setup libraries
Set simulation par.
Run si...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
PRESTO
123456
789
FILE_TYPE=HDT_PLIB;
TIME=Thu Dec 10 10:45:33 1992...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
• PRESTO important concepts
• CAD data extr...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
PRESTO important concepts
• Design components
• Design nets
• Cross...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Design Components
Design components are physical devices of your de...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Design nets
Design nets are physical interconnections (usually show...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Crossection
is the geometrical/physical description of the
transver...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Signal parameters
20%
80%
Overshoot
Undershoot
Rise edge
Fall edge
...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Stripline and microstrip
dielectric1
metal plane metal plane
conduc...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Signal reflections due to impedance
mismatch
Wave reflection occurs...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Crosstalk
Crosstalk is a phenomenon that occurs when two or more tr...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Simultaneous Switching Noise (SSN)
This phenomenon is due to curren...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Physical Model
Describes:
– the pinout of the component package
– t...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Electrical Model
– models the electrical behavior of driver/receive...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
CAD data extraction
2-1
• PRESTO important ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
CAD data extraction (1)
1. Execute extract command from the PRESTO ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
CAD data extraction (2)
• Supported CAD format are:
– ALLEGRO (Cade...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
PRESTO input format
3-1
• PRESTO important ...
PRESTO 3.2 Training Course
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PRESTO input format
• PRESTO input format is composed by four files...
PRESTO 3.2 Training Course
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PRESTO Netlist File (.PNF)
• Describes the component list and attri...
PRESTO 3.2 Training Course
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PRESTO Netlist File (2)
Some attributes of the component list can b...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
PRESTO Geometric File (.PGF)
• Describes the physical topology of t...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
PRESTO Crossection File (.PXF)
• Describes the transverse section o...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
PRESTO Copper Areas File (.PSF)
• Describes the copper areas of the...
PRESTO 3.2 Training Course
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Training course outline
Library Setup
4-1
• PRESTO important concep...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Library setup
• Libraries (both physical and electrical) are organi...
PRESTO 3.2 Training Course
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Library priority
• During the model link phase, PRESTO begins the s...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
Special nets
5-1
• PRESTO important concept...
PRESTO 3.2 Training Course
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Special Nets
• Special nets are power and ground nets
• Special net...
PRESTO 3.2 Training Course
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Special net identification
• A net can be specified as Special in t...
PRESTO 3.2 Training Course
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Special net management
During the simulation, the special nets are ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
Aliases setup
6-1
• PRESTO important concep...
PRESTO 3.2 Training Course
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Aliases
Aliases define equivalencies between two names of component...
PRESTO 3.2 Training Course
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Aliases type
• Library aliases
– can be defined for component names...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Library aliases
• Library aliases are stored in the same library of...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Design aliases
• Design aliases can have only local meaning (curren...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
7-1
Signal stimuli creation
• PRESTO import...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Signal stimuli creation
Used to specify the switching time features...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Stimuli Setup
Stimulus bit-sequence can be specified
directly or ca...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Stimuli LAB
• create the following stimuli declarations:
– a 50 MHz...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
Signal mask creation
8-1
• PRESTO important...
PRESTO 3.2 Training Course
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Signal mask creation
• Compliance analysis of signal is performed w...
PRESTO 3.2 Training Course
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Uniform masks
• These masks are well suited to check noise
amplitud...
PRESTO 3.2 Training Course
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PWL masks
• PWL masks are suitable to check integrity of
switching ...
PRESTO 3.2 Training Course
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PWL mask defined by %
• The maximum working frequency specification...
PRESTO 3.2 Training Course
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PWL mask defined by value
• The maximum working frequency specifica...
PRESTO 3.2 Training Course
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Mask shape definition (1)
Mask name
maximum working frequency: a
ma...
PRESTO 3.2 Training Course
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Mask shape definition (2)
As example, the procedure to create a RU ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Masks LAB
create the following Mask definitions:
– a uniform mask t...
PRESTO 3.2 Training Course
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Training course outline
Net class definition
9-1
• PRESTO important...
PRESTO 3.2 Training Course
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Net Class definition
A Net Class defines a set of parameters that w...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Net Classes application
• to check quiet nets (like power supply ne...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Net Class reference values
• for Uniform masks, the two values have...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
Simulation setup
10-1
• PRESTO important co...
PRESTO 3.2 Training Course
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Simulation setup
1) set library paths and aliases
2) Identify power...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Set library paths and aliases
• System libraries are automatically ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Identifying missing components
If some components are missing in li...
PRESTO 3.2 Training Course
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Default model facility
If some components are not described in libr...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Special nets
Special nets can be identified by the user or by
means...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Net Class assignment
• A Net Class specifies the type of analysis t...
PRESTO 3.2 Training Course
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Basic simulation parameters setup
Specify the use of default models...
PRESTO 3.2 Training Course
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Training course outline
Running simulation
11-1
• PRESTO important ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Running the simulation
To start the simulation choose the command R...
PRESTO 3.2 Training Course
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Training course outline
Looking at simulation results
12-1
• PRESTO...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Looking at simulation results
• Compliance analysis ASCII report fi...
PRESTO 3.2 Training Course
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Compliance analysis report file
** COMPLIANCE ANALYSIS REPORT **
De...
PRESTO 3.2 Training Course
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Graphical analysis
• Waveforms can be displayed with SIGHTS
• Activ...
PRESTO 3.2 Training Course
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Waveforms can be referred by component/pin_name or by the
net_name ...
PRESTO 3.2 Training Course
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Plot and Plot by net (old Sights)
Single waveforms can be plotted w...
PRESTO 3.2 Training Course
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Eye diagrams (old Sights only)
Eye diagrams are obtained by superim...
PRESTO 3.2 Training Course
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Other useful functionalities of SIGHTS
(Old Unix version only)• Mul...
PRESTO 3.2 Training Course
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Training course outline
Output waveform postprocessor
13-1
• PRESTO...
PRESTO 3.2 Training Course
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Output waveform postprocessor (1)
Overshoots, undershoots, rise and...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
1) Run the simulation with graphic output as option
2) Set the para...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Pin-to-Pin delay
• Activated by View->Delay Report
• Evaluates the ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
Simulating crosstalk
14-1
• PRESTO importan...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Simulating crosstalk
• Check for noise between two or more parallel...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Crosstalk analysis flow
1 2 3
10 20 30
1
2
3
10
20
30
1
2
3
10
20
3...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Extracting coupled structures
• Coupled structures are extracted by...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Crosstalk structures
Min Length = 50 mm MaxDistance = 2 mm Resoluti...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Victim nets
• Optionally, during the analysis, a selected net (vict...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Electromagnetic Field Solver
• The PRESTO electromagnetic field sol...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Running crosstalk analysis
• Run the Crosstalk Preprocessor with th...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Crosstalk analysis results
• Results can be obtained in ASCII or gr...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
Simulating SSN
15-1
• PRESTO important conc...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
SSN analysis
• Check for noise caused by drivers switching
simultan...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
SSN analysis flow
t
t
t
• SSN macromodels of ICs are built up
autom...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Percentage of switching drivers (1)
How many drivers switch
simulta...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Percentage of switching drivers (2)
PRESTO allows two approaches:
a...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Running SSN analysis
• Set SSN button in the Simulation Setup windo...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
SSN report
• The drivers to be set quiet are automatically chosen
b...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
SSN results
• Results can be obtained in ASCII or graphical
way, ac...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
Physical library
16-1
• PRESTO important co...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Physical library
• Contains the physical model descriptions.
• Data...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Physical Model
Describes:
– the pinout of the component package
– t...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Physical model types
• Resistors, capacitors, inductors, diodes
• I...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Physical model definition
The model description is done by means of...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Physical Model Description format (PMD)
FILE_TYPE=HDT_PLIB;
TIME= x...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
R,L,C, Diodes
• These are two-pin models
• Only one electrical mode...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Integrated circuits
• One electrical model has to be assigned to ea...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Example of IC description
1 RECEIVER ac_rc vcc gnd
2 RECEIVER ac_rc...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Programmable Logic Devices (PLD)
• Their I/O description is not fix...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Connectors (CON)
• Like PLD, the connector configuration is design
...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Connectors (2)
• Specific electrical models can be utilized to take...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Connectors (3)
• The component name of connectors is specified like...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Example of connector model
1 RECEIVER ac_rc 5 0
2 RECEIVER ac_rct 5...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Special components
• These models describe the component as a black...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Library management
• To insert a model in library:
– Create a model...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Importing and exporting models
• To import a model from an ASCII fi...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
Electrical library
17-1
• PRESTO important ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Electrical library
• Contains the electrical model descriptions
(dr...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Modeling capabilities
• The models are described as .SUBCKT circuit...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Model types
• Driver/Receiver
– 4-pin models
– Suitable for ICs/PLD...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Receiver Model
sources,
passive elem.,
measures,
power node
ground ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Example of simple CMOS receiver model
in
out
vcc
gnd
Cin
STF
Pvcc
P...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Driver model
sources,
passive elem.,
measures,
power node
ground no...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Example of CMOS driver model
out
vcc
gnd
Cout
2
10
20
Pvcc
Vcomp
E1...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Special components
component
power rail
ground rail
core
Any Sprint...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Example of special component model
AC02 (four NOR):
1234567
gnd
vcc...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Importing and exporting models
• To import a model from an ASCII fi...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
• PRESTO important concepts
• CAD data extr...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Performing a “What-If?” analysis
• Check the effects of small modif...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Friendly Graphic User Interface
Layout optimisation
18-3
Click with...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Component optimisation
Layout optimisation
18-4
Currently deleted/ ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Segment Optimisation
Electrical Segment
insertion window
Currently ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Training course outline
• PRESTO important concepts
• CAD data extr...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
EmiR analysis flow
EMI analysis
A Signal Integrity
simulation with ...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Time domain parameters setup
The simulation time window is complete...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
EMI simulation characteristic
• The Cross Talk analysis is not comp...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
EmiR setup
Anechoic
chamber
analysis
Run EmiR
analysis
Semi-anechoi...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Anechoic chamber analysis
Select low frequency
algorithm
Provide al...
PRESTO 3.2 Training Course
Version 1.0 HDT proprietary
Semi-anechoic chamber analysis
Use a fixed height for the
antenna o...
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Presto training course_1999

TRAINING COURSE SLIDES OF PCB POST-LAYOUT SIMULATOR PRESTO
Published on: Mar 4, 2016
Published in: Technology      
Source: www.slideshare.net


Transcripts - Presto training course_1999

  • 1. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO 3.2 T A I N G I N Version 1.0 May 1999 The contents of this training course are proprietary data of High Design Technology. Use or disclosure of the information contained in this document is allowed only under written authorization of High Design Technology. High Design Technology Copyright 1998 High Design Technology. All rights reserved.
  • 2. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO History 1988 Development starting 1990 SPRINT & SIGHTS High perfomance simulation & modeling 1992 PRESTO Rel 1.1 Compliance analysis 1993 PRESTO Rel 1.2 + Crosstalk analysis 1994 PRESTO Rel 2.0 + SSN analysis + new GUI 1995 PRESTO Rel 2.1 + EmiR + THRIS integration 1996 PRESTO Rel 2.2 + EmiR-Cable + What-If Analysis 1997 PRESTO Rel 3.0 + ModEnv modeling+ IBIS interface 1998 PRESTO Rel 3.1 + Lossy lines and Modal method 1999 PRESTO Rel 3.2 + Net class propagation + New error management Introduction i
  • 3. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO flow Extract data Setup libraries Set simulation par. Run simulation View results 1 2 3 4 5 Introduction ii
  • 4. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO 123456 789 FILE_TYPE=HDT_PLIB; TIME=Thu Dec 10 10:45:33 1992 COMPONENT=AC04, 74AC04; FAMILY=FACT; PACKAGE=DEFAULT, DIP14, SOIC14; FACTORY=DEFAULT; TYPE=IC; NPINS=14; BEGIN_PIN FACT_DR24_P=2,4,6,8,10,12; FACT_RC_P=1,3,5,9,11,13; FACT_GND_P=7; FACT_VCC_P=14; END_PIN; BEGIN_FUNCTION DRIVER=2,4,6,8,10,12; RECEIVER=1,3,5,9,11,13; POWER_FACT=14; GROUND_FACT=7; END_FUNCTION; END. Driver Receiver SSN report Compliance analysis report Overshoots undershoots rise and fall time report Electrical models Physical models Board layout data Introduction iii 398.00 399.00 400.00 401.00 402.00 403.00 404.00404.40 TIME[nS] -2.00 V -1.75 V -1.50 V -1.25 V -1.00 V -0.75 V -0.50 V V(116) 70.00 80.00 90.00 100.00 110.00 120.00 130.00 140.00 150.00 160.00 170.00 180.00 -5.00V -4.00V -3.00V -2.00V -1.00V 0.00V 1.00V 2.00V 3.00V 4.00V 5.00V 6.00V 7.00V 8.00V EMC reports:Con ducted and radiated emissions What-If
  • 5. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1-1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 6. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO important concepts • Design components • Design nets • Crossection • Signal parameters • Striplines • Microstrips • Reflections due to impedance mismatch • Crosstalk noise • Simultaneous Switching Noise (SSN) • Physical models • Electrical models PRESTO important concepts 1-2
  • 7. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Design Components Design components are physical devices of your design (resistors, capacitors, integrated circuits, connectors, etc). A component is characterized by: – part name: specifies the type of device. This is the identifier used to search components in libraries – instance name: more than one component having the same part name can be present in your design. The instance name identifies univocally the component. – value: specifies the value of the component (if any). It is used for resistors, inductors and capacitors. – pins: a component has one or more pins where design nets are connected – package: it is the name of the component package. Different packages can have different electrical behaviors even if the part name is the same PRESTO important concepts 1-3
  • 8. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Design nets Design nets are physical interconnections (usually showing low DC resistance) between two or more pins of components implemented by metal traces. – Net name is a name that identifies the entire net – Special nets are power and ground nets – Net segments are linear sections of the trace – Vias are metalized through-holes used to connect net segments belonging to different layers of the crossection – Bend a junction between two net segments defining a corner – T-junction a junction between three net segments – Sub-net a subsection of a net composed by one or more segments connecting two T-junctions or a T-junction with a pin or two pins. A net can also be implemented by a metal plane PRESTO important concepts 1-4
  • 9. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Crossection is the geometrical/physical description of the transverse section of the board or MCM y-direction traces x-direction traces metal plane dielectric PRESTO important concepts 1-5
  • 10. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Signal parameters 20% 80% Overshoot Undershoot Rise edge Fall edge Overshoot Undershoot 0% 100% Rise time Fall time PRESTO important concepts 1-6
  • 11. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Stripline and microstrip dielectric1 metal plane metal plane conductor conductor conductor conductor dielectric2 metal plane metal plane dielectric3 conductor dielectric1 dielectric2 dielectric1 metal plane metal plane conductor conductor conductor conductor dielectric2 air conductor dielectric1 air microstrips striplines PRESTO important concepts 1-7 Examples of:
  • 12. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Signal reflections due to impedance mismatch Wave reflection occurs when the impedance at receiver or driver ends is not matched to the characteristic impedance of the line. In this case, a percentage of the incident wave is reflected back and the same phenomenon happens at the other end of the line. Reflections also occur when geometrical /physical discontinuities affect the interconnection (vias, bends, changing of layer). Due to the complexity of the interconnection topologies and the non- linearities of drivers and receivers (V/I curve, clamping diodes), the effects of reflections on signals can be pratically analysed only through simulation. PRESTO important concepts 1-8
  • 13. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Crosstalk Crosstalk is a phenomenon that occurs when two or more traces (usually belonging to different nets) follow parallel paths. In this case, an edge travelling on one of the traces couples some of its energy to the others, causing noise (far-end and near-end crosstalk). Crosstalk depends on both electrical (signal edge shape) and geometrical (coupling length and crossection) parameters. The crossection of coupled structures is usually analyzed by means of a 2-D electromagnetic field solver. PRESTO important concepts 1-9 propagating edge disturbing line victim line near-end crosstalk far-end crosstalk
  • 14. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Simultaneous Switching Noise (SSN) This phenomenon is due to current pulses caused by switching drivers. The current pulses, flowing through lines or parasitic inductances, causes an impulsive drop of voltage on the power supply rails. If several drivers switch simultaneously, this voltage drop can exceed the noise margins of nets at quiet state, causing undesired switching. It is possible to distinguish two levels of SSN: - Inside the component package: it is caused by the parasitic effects of the power supply pins of the package. It is difficult to control. - Outside the component package: it is caused by the non-ideal power supply distribution on the board or MCM. It can be reduced by means of decoupling capacitors. PRESTO important concepts 1-10 PRESTO allows the simulation of both causes of SSN noise allowing the verification of decoupling capacitors effectiveness .
  • 15. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Physical Model Describes: – the pinout of the component package – the function of the pin (driver, receiver, power supply, etc) – the name of the electrical model to be utilized during the simulation 1 2 3 4 5 6 7 8 9 FILE_TYPE=HDT_PLIB; TIME=Thu Dec 10 10:45:33 1992 COMPONENT=AC04, 74AC04; FAMILY=FACT; PACKAGE=DEFAULT, DIP14, SOIC14; FACTORY=DEFAULT; TYPE=IC; NPINS=14; BEGIN_PIN FACT_DR24_P=2,4,6,8,10,12; FACT_RC_P=1,3,5,9,11,13; FACT_GND_P=7; FACT_VCC_P=14; END_PIN; BEGIN_FUNCTION DRIVER=2,4,6,8,10,12; RECEIVER=1,3,5,9,11,13; POWER_FACT=14; GROUND_FACT=7; END_FUNCTION; END. PRESTO important concepts 1-11
  • 16. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Electrical Model – models the electrical behavior of driver/receivers – uses the Spice-like syntax of SPRINT simulator – model parameters can be extracted from datasheets, Spice simulations or measures (V/I curves or TDR) Driver Receiver S_MODEL = RECEIVER; DESCRIPTION = FACT receiver; BEGIN_SUBCKT *************** FACT RECEIVER MODEL *********** * creation date: 19 Jan 1993 * * maximum simulation time step: 100ps * recommended simulation time step <= 50ps * ideal logic output signal (0 1) ********************************************* .SUBCKT FACT_RC 1 2 10 20 * in out VCC GND E1 2 0 1 20 THR(2.5V 0 1) RO 2 0 10MEG CIN 1 0 4.5PF PVCC 1 10 0V 0MA 0.55V 0MA 0.62V 0.1MA 0.74V 1MA 0.83V 5MA 0.87V 10MA + 0.9V 15MA 1V 40MA C=1P PGND 1 20 -0.9V -50MA -.89V -20MA -.83V -10MA -.792V -5MA -.763V -2.5MA + -.731V -1MA -.69V -.3MA -.647V -.1MA -.6V -.02MA -.5V -.01MA 0 0 C=1P .ENDS FACT_RC ********************* END_SUBCKT PRESTO important concepts 1-12
  • 17. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline CAD data extraction 2-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 18. PRESTO 3.2 Training Course Version 1.0 HDT proprietary CAD data extraction (1) 1. Execute extract command from the PRESTO user interface: Run->CAD Extractor 2. Locate the CAD files that have to be processed: the extractor will store the PRESTO files in the current working directory CAD data extraction 2-2 .pnf file .pgf file .pxf file .psf file
  • 19. PRESTO 3.2 Training Course Version 1.0 HDT proprietary CAD data extraction (2) • Supported CAD format are: – ALLEGRO (Cadence) – BOARDSTATION (Mentor) – SPECCTRA (CCT) – VISULA (Zuken) – THEDA (Incases) – PADS (Pads Software) – P-CAD (ACCEL Technologies) • For further details please refer to the PRESTO User Manual CAD data extraction 2-3
  • 20. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline PRESTO input format 3-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 21. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO input format • PRESTO input format is composed by four files: – PRESTO Netlist File (design.pnf) – PRESTO Geometric File (design.pgf) – PRESTO Crossection File (design.pxf) – PRESTO Copper Areas (design.psf) PRESTO input format 3-2
  • 22. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO Netlist File (.PNF) • Describes the component list and attributes • Describes the net list and attributes DEFAULTS UNITS_PER_INCH = 1000; END_DEFAULTS SUMMARY NUM_NETS = 22; NUM_COMPONENTS = 17; NUM_CONDUCTORS = 6; END_SUMMARY COMPONENTS IC23 = 74AC04-2, PKG = SOIC14, XCMP = 6300, YCMP = 5400; U4 = L20-1, PKG = DIP24_4, XCMP = 3200, YCMP = 6600; ............. NET_DESCRIPTION RESETN = IC24 1, U4 5; RESET = IC24 2, U7 5; ............ END_NET_DESCRIPTION END_BOARD user unit declaration design summary component description net connectivity description PRESTO input format 3-3
  • 23. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO Netlist File (2) Some attributes of the component list can be modified by the user: • Choose Part Editor from Run menu • You can assign an alternate name for both the part name and package name to be utilized during the search procedure in library • You can assign/modify the value property of passive components (R,L,C). Usually this parameter is automatically extracted from the CAD interface. PRESTO input format 3-4 Note: To address names in library, it is suggested to use the ALIAS definition (see later) instead of Alt.name and Alt.pack. Infact ALIAS definitions doesn’t change if a new CAD extraction is done.
  • 24. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO Geometric File (.PGF) • Describes the physical topology of the nets P_D: 37, 75, 80, 95; V_D: 75; WDH: 12, 50, 100; NET: RESETN; SEG: 0, 0, 5225, 5550, 5600, 5550; VIA: 0, 5225, 5550; CMP: IC24, 1, 0, 100000, 5600, 5550; SEG: 0, 3, 5225, 5550, 3750, 5550; SEG: 0, 3, 3750, 5550, 3675, 5625; SEG: 0, 3, 3675, 5625, 3675, 6150; SEG: 0, 3, 3675, 6150, 3575, 6150; SEG: 0, 3, 3575, 6150, 3525, 6200; SEG: 0, 3, 3525, 6200, 3200, 6200; CMP: U4, 5, 1, 111111, 3200, 6200; NET: RESET; SEG: 0, 0, 5600, 5500, 5675, 5500; SEG: 0, 0, 5675, 5500, 5700, 5525; SEG: 0, 0, 5700, 5525, 5700, 6150; types of pads via diameters trace widths net name net description in term of vias, pads and segments PRESTO input format 3-5
  • 25. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO Crossection File (.PXF) • Describes the transverse section of the board or MCM substrate INS: AIR,0,,1,0,0; CND: COPPER,1.44,TOP,595900,1,0; INS: FR-4,9.84252,,4.7,2,1; SHL: COPPER,1.44,VEE,595900,3,1; INS: FR-4,12,,4.7,4,2; CND: COPPER,1.44,S1,595900,5,2; INS: FR-4,12,,4.7,6,3; CND: COPPER,1.44,S2,595900,7,3; INS: FR-4,12,,4.7,8,4; SHL: COPPER,1.44,GND,595900,9,4; INS: FR-4,9.84252,,4.7,10,5; CND: COPPER,1.44,BOTTOM,595900,11,5; INS: AIR,0,,1,12,6; conductor layer declaration insulator layer declaration shield layer declaration (filled or grid metal plane) Note: Some parameters of the crossection (dielectric constant, layer thickness, etc) can be modified. In this way it is possible to perform WHAT IF analysis, running multiple simulations with different parameters PRESTO input format 3-6
  • 26. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PRESTO Copper Areas File (.PSF) • Describes the copper areas of the board like power planes, partial or splitted metallization and so on. 3-7 Note: Metal planes will be managed as a grid of lossy transmission lines in Q2/99 PRESTO input format
  • 27. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Library Setup 4-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 28. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Library setup • Libraries (both physical and electrical) are organized in a database to insure a fast search of models • System libraries are shipped with the software and cannot be modified • More than one electrical/physical library can be open at the same time • Two additional levels (other than System library level) can be used to define libraries: User level or Group level. system libraries paths user/group physical libraries list user/group electrical libraries list Library Setup 4-2
  • 29. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Library priority • During the model link phase, PRESTO begins the search of model description starting from the user libraries sorted in the same order they are listed in the window and then in the group and system libraries respectively, if models are not found in lower level libraries. • The Library Setup window (available within the Setup menu) allows the user to add library paths, delete them or change the priority. Note: It is suggested to use group level libraries to define models or library aliases that have general meaning inside a group of designers. For example, the Group level library could contain the standard components available in warehouse, while the user level libraries could be used to define aliases or/and to contain models of semicustom ICs (design specific components). Library Setup 4-3
  • 30. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Special nets 5-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 31. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Special Nets • Special nets are power and ground nets • Special nets can be: – distributed: wired power supply nets (implemented by metal traces) are translated into transmission line equivalents as well as other nets. – collapsed: the power supply net distribution is collapsed in one single electrical node. Metal planes of power supply are automatically collapsed. • Special nets require a voltage value assigned Special nets 5-2
  • 32. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Special net identification • A net can be specified as Special in two ways: – if the power supply net name is already known, you can setup directly this property by means of the commands available in the Net Editor window (available within the Test Control menu) – The command Search Special Net is available in the Net Editor window: it uses the information stored in the physical libraries to identify nets that connect power and ground pins of components Note: The voltage value associated to the special net must always be specified by the user before running the simulation Special nets 5-3
  • 33. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Special net management During the simulation, the special nets are connected to electrical models of power supply: • If the special net is collapsed in a single electrical node, the power supply model is connected to the node • If the special net is distributed, the power supply model(s) is(are) connected in the network in correspondence of component pins with the property TYPE=GENPOWER (see physical models properties). If no pins have attribute GENPOWER, the special net is automatically turned to collapsed type Note: The power supply model is a two pin electrical model (the second pin is ground) and must be available in the electrical library . It can be described as an ideal power supply (ideal independent voltage generator) or can include parasitic effects as noise (ripple, burst, non-linear output resistance) Special nets 5-4
  • 34. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Aliases setup 6-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 35. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Aliases Aliases define equivalencies between two names of components or packages • Different CAD environments can utilize different names for the same component (for example: DIP14, DIP14_4, DIP14CA) • Different manufacturers can identify their components with a specific prefix/suffix (for example: 74AC08, SN74AC08) • Designers sometimes utilize internal codes to identify component or package names (for example warehouse codes) Aliases are used by PRESTO to identify a component of the library having a part name that is not equal to the part name specified in the design netlist (.pnf file). The same applies for package names. Aliases setup 6-2
  • 36. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Aliases type • Library aliases – can be defined for component names only. The alias definition (netlist part name pointing to a library part name) is inserted in the same physical library where the pointed part name is stored • Design aliases – can be defined for component or package names. The alias definition is stored in a specific file (.ali) within the current directory and its validity is limited to the current design. Aliases setup 6-3
  • 37. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Library aliases • Library aliases are stored in the same library of the pointed physical model. • From a user point of view, it is equivalent to create a new physical description of the component with a different name. • Library aliases cannot point to another alias definition. • Library aliases can be used from many designers at the same time (it is only necessary to link the physical library). Part or package name of the component in netlist Part or package name of the component in library Design aliases menu is activated through the command Alias Manager-> Library Aliases available within the Model menu Aliases setup 6-4
  • 38. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Design aliases • Design aliases can have only local meaning (current design) • PRESTO first replaces the names specified in the netlist with the names pointed by the design aliases (creating a new key to access the physical library) and then starts the search in library Part or package name of the component in netlist Part or package name of the component in library Design aliases menu is activated through the command Alias Manager-> Design Aliases from the Model menu Aliases setup 6-5
  • 39. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline 7-1 Signal stimuli creation • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 40. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Signal stimuli creation Used to specify the switching time features of drivers during the simulation. A stimulus is characterized by: – stimulus name (for example: stim1) – binary bit sequence (for example: 10010110111) – working bit rate expressed in Mbit/s (for example: 150) The time of the single bit is calculated as: tbit (ns) = 1000 bit-rate (in Mbit/s) tbit Signal stimuli creation 7-2
  • 41. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Stimuli Setup Stimulus bit-sequence can be specified directly or can be contained in an ASCII file it is possible to delete, modify or create a new stimulus declaration using the commands of the Stimulus menu Note: If the simulation time window is longer than the stimulus duration, the bit- sequence will be automatically repeated. Signal stimuli creation 7-3
  • 42. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Stimuli LAB • create the following stimuli declarations: – a 50 MHz clock with 50% duty-cycle – a 10 Mbit/s stimulus with bit-sequence 1011011 – a 20 Mbit/s stimulus with bit-sequence 110110101 specified in a file called filestim – a 100 MHz clock with 20% duty cycle Signal stimuli creation 7-4
  • 43. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Signal mask creation 8-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 44. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Signal mask creation • Compliance analysis of signal is performed with respect to user-defined masks. Possible shapes: – Uniform masks – PWL masks (Piece-Wise Linear) • Masks are defined with respect to a reference signal • Signals violating the masks during the simulation are reported in the .rep file Signal mask creation 8-2
  • 45. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Uniform masks • These masks are well suited to check noise amplitude on signals at fixed voltage values (power supply nets or victim nets during a SSN or crosstalk analysis) • The signal voltage used as reference is specified in the net class definition. • Only two noise margins (lower and upper) have to be defined Upper Margin Lower Margin Reference value Signal mask creation 8-3 added noise
  • 46. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PWL masks • PWL masks are suitable to check integrity of switching signals • PWL masks behaviors can be defined graphically by 4 shapes: – Rising Upper edge (RU) – Rising Lower edge (RL) – Falling Upper edge (FU) – Falling Lower edge (FL) • PWL masks are defined: – by % – by value • It is always necessary to specify a maximum operating frequency RL mask RU mask FU mask FL mask A B C D E F G H reference y t bit-time bit-time Signal mask creation 8-4
  • 47. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PWL mask defined by % • The maximum working frequency specification is necessary to draw the mask shapes • The reference signal ranges always between 0 and 1 (0-100%) • In the net class definition (where the mask will be used) the user has to set the actual reference signal swing: the mask amplitude will be automatically scaled These masks can be utilized for more than one net class declaration, because their shape applies to whatever signal swing. reference y t 0% 100% y t V2 V1 net class definition: High_value = V1 Low_value = V2 as you define it as PRESTO actually simulates it Signal mask creation 8-5
  • 48. PRESTO 3.2 Training Course Version 1.0 HDT proprietary PWL mask defined by value • The maximum working frequency specification is necessary to draw the mask shapes • The reference signal swing is user-defined • The net class definition utilizing a PWL mask defined by value will set the actual reference signal swing to the value specified in the mask: the mask amplitude will not be scaled in this case These masks can be utilized to check signals with well specified noise tolerances. y t V2 V1 net class definition: swing value are defined by the mask as you define it as PRESTO actually simulates it y t V2 V1 Signal mask creation 8-6
  • 49. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Mask shape definition (1) Mask name maximum working frequency: a mask can be used to check signals switching at a bit rate lower or equal to the maximum working frequency click here to start the shapes creation of a new mask click on these buttons to modify a specific mask shape By % or By value selection Signal mask creation 8-7
  • 50. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Mask shape definition (2) As example, the procedure to create a RU shape is shown: 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 TIME[nS] -1.00 V -0.50 V 0.00 V 0.50 V 1.00 V 1.50 V 2.00 V 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 TIME[nS] -1.00 V -0.50 V 0.00 V 0.50 V 1.00 V 1.50 V 2.00 V 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 TIME[nS] -1.00 V -0.50 V 0.00 V 0.50 V 1.00 V 1.50 V 2.00 V 1) The reference rising waveform will be displayed: the marker of the starting point is forced to move only on the Y axis. 2) A mask segment is defined by positioning the marker on the chosen point and by pressing the left button of the mouse; now the marker can only move at the right of the selected point and a hairline will connect the marker with this point. 3) This procedure is repeated during the selection of the other breakpoints. The total number of breakpoints can range between 3 and 20. After choosing the last point, click on the right button of the mouse to exit. Signal mask creation 8-8
  • 51. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Masks LAB create the following Mask definitions: – a uniform mask to check 5V power supply signals with 5% tolerances – a PWL mask by percentage with: » max working frequency = 10Mbit/s » noise tolerances on steady state values = 10% swing » noise tolerances for overshoots = 20% swing » other parameters are free – a PWL mask by value for CMOS signals with: » max working frequency = 20Mbit/s » noise tolerances = 1.25V (reference signal= 0-5V) » max delay allowed = 3ns Signal mask creation 8-9
  • 52. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Net class definition 9-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 53. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Net Class definition A Net Class defines a set of parameters that will be utilized to check signals during the simulation: – the stimulus assigned to the driver – the mask used to check the signal – the reference values used to scale and shift uniform or PWL signal masks – the delay time of the stimulus before starting the signal checks (to allow the setup of the start-up transient) t stimulus td t mask generator net driver net under analysis rec. 1 rec. 2 rec. n mask violation t V2 V1 1 0 1 0 RESULTS checker td WARNING: The working frequency of the used stimulus within a net class definition cannot exceed the maximum working frequency of the signal mask. Net class definition 9-2
  • 54. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Net Classes application • to check quiet nets (like power supply nets, victim nets during a xtalk or SSN analysis) – the mask type is Uniform – the first bit of the stimulus assigned to the class specifies the steady state level for victim nets (it has no meaning for power supply nets) »01101101 “0” logic state »11101100 “1” logic state • to check switching nets – the mask type is PWL (by % or by value) – the bit sequence is applied to the driver as specified by the stimulus definition Net class definition 9-3
  • 55. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Net Class reference values • for Uniform masks, the two values have to be identical and specify the absolute voltage value to be applied to check noise amplitude on quiet nets . • for PWL by % masks, the two values are used to scale the mask parameters (amplitude only) during the simulation. • for PWL by value masks, the two values are automatically set to the masks reference signal values. reference values Net class definition 9-4
  • 56. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Simulation setup 10-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 57. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Simulation setup 1) set library paths and aliases 2) Identify power supply nets and set their voltage values 3) assign class to nets 4) set simulation parameters Before running a simulation follow these steps: Simulation setup 10-2
  • 58. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Set library paths and aliases • System libraries are automatically set by means of the environment variable HDTTOOLS • Physical and electrical libraries must be selected by the user through the Library Setup window. • Aliases (both library and design) must be specified. If all components already have the right name in library, the alias setup is not required. If one or more components are not identified during the simulation, an error occurs: “Error: physical models missing in library” Simulation setup 10-3
  • 59. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Identifying missing components If some components are missing in library, the .log file will report their names: part-name, package name and factory as specified in the netlist part-name, package name and factory name used to search in library (design aliases are applied before the search starts) component that has been found in library: component that has not been identified: “Component 100125-1 PDIL24_4 Default found as 100125 DIP24 Default in library mylib.plb” “Warning: Component 100124-1 PDIL24_4 Default searched as 100124-1 DIP24 Default not Found!” library name Possible actions: • create a physical description of the component or • define an alias or • utilize the default model facility. Simulation setup 10-4
  • 60. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Default model facility If some components are not described in library,a list of their pins is created. You can assign default I/O driver or receiver models (TTL, CMOS, ECL, Low voltage) to each pin of the missing component list using the Default Model Editor window without the definition of a new specific physical model. Note: Remember to set the “Default Models”button in the Simulation Setup window before running the simulation again Simulation setup 10-5
  • 61. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Special nets Special nets can be identified by the user or by means of the “Search Special Nets” command available on the Net Selector window. This command utilizes the information contained in the physical library to identify the nets connected to power and ground pins of components. In order to work properly, it is required to set the libraries paths before running the Search Special Nets command. In any case, you must specify the voltage value and the collapsed/distributed property for each special net. Simulation setup 10-6
  • 62. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Net Class assignment • A Net Class specifies the type of analysis to perform on the net. • Any net must have a net class assigned before running the simulation. • A default class is automatically set for the nets without a specific class assigned by the user. • A class can be assigned: – by the user using the Net Editor window; – automatically using the command “Automatic Net Class Assignment” available under the Nets Attributes menu of the Net Selector window. In this case, the default net classes associated to the drivers in the physical libraries will be assigned to the nets. In order to work properly, it is required to set the libraries paths before running the Automatic Net Class Assignment command. Simulation setup 10-7
  • 63. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Basic simulation parameters setup Specify the use of default models for components not available in library Xtalk, SSN switches: enable these two types of analysis Resolution of the graphical output waveforms: 300-1000 samples give a good resolution in normal situations. This number must be increased to maintain a good resolution in case of zoom or eye-diagram plots. In this case the output file can be very large. Simulation time step: a value between 10 and 100 (ps) is suggested for normal situations The simulation time window can be automatically evaluated on the basis of the lengths of the bit- sequences assigned as stimuli to the drivers or can be selected by the user Simulation setup 10-8 Enable the simulation of the modifications made with the What-If tool
  • 64. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Running simulation 11-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 65. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Running the simulation To start the simulation choose the command Run Simulation from the Run menu. – phase 1: » translates the physical data of layout traces into transmission lines, » checks that all physical models are included in library, » calls the EM field solver if crosstalk analysis is activated – phase 2: » imports in the netlist the electrical models (with its right package model), » sets simulation parameters – phase 3: » SPRINT executes the transient simulation of the design, » produces the output file Errors are stored in the prerr.err file (simulation phase) and uierr.err (user interface). Messages and warnings are stored in the .log file. Running simulation 11-2
  • 66. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Looking at simulation results 12-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 67. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Looking at simulation results • Compliance analysis ASCII report file • Graphical analysis with SIGHTS – plot, mplot, plot_by_net, etc – eye diagram (for Unix-based workstations only) Looking at simulation results 12-2
  • 68. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Compliance analysis report file ** COMPLIANCE ANALYSIS REPORT ** Design name: tutorial Net name Upper mask Lower mask I ntegrated Violation Violation Violation Error ------------------------------------------------------------------------------------------------ VCC * 10.972890 RESET * 1.485747 DATA * 1.484746 RESETN * 1.483746 ------------------------------------------------------------------------------------------------ DATA1 * 1.483746 PULLUP * 1.060050 PULLDOWN * 0.705617 FANIN * 0.390969 ------------------------------------------------------------------------------------------------ VEE OUTECLP1 GND OUTECLM1 • Lists the nets not passing the compliance analysis test (masks violations). • The check is performed on receiver pins only. • The file reports the mask that has been violated (upper or lower) and prints a number representing the total integrated violation error Looking at simulation results 12-3
  • 69. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Graphical analysis • Waveforms can be displayed with SIGHTS • Activated by the command: View->results->Graphical it allows the plotting of waveforms • The following description refers only to particular functions of SIGHTS suitable for S.I. Analysis • For Unix based workstation there is an other old (no XVT based) version of Sights (Run->Sights) that allows a larger number of functionality. For a general description please refers to “SIGHTS User Manual Looking at simulation results 12-4
  • 70. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Waveforms can be referred by component/pin_name or by the net_name they belonging. The related netclass masks can be added to the display. Background can be white or black. An “EVAL” function that allows you to display waveform values is available. 70.00 80.00 90.00 100.00 110.00 120.00 130.00 140.00 150.00 160.00 170.00 180.00 TIME[nS] -5.00V -4.00V -3.00V -2.00V -1.00V 0.00V 1.00V 2.00V 3.00V 4.00V 5.00V 6.00V 7.00V 8.00V #U4_1 #MASKdefaultcmos_L #MASKdefaultcmos_U #IC23_4 Plot and Plot by net (new Sights) 12-5
  • 71. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Plot and Plot by net (old Sights) Single waveforms can be plotted with the command: “Plot <testpoint list>“. The command Plot by net (“Plot -n <netname list>“) plots all the testpoints of a net with the related masks 70.00 80.00 90.00 100.00 110.00 120.00 130.00 140.00 150.00 160.00 170.00 180.00 TIME[nS] -5.00V -4.00V -3.00V -2.00V -1.00V 0.00V 1.00V 2.00V 3.00V 4.00V 5.00V 6.00V 7.00V 8.00V #U4_1 #MASKdefaultcmos_L #MASKdefaultcmos_U #IC23_4 Looking at simulation results 12-5bis
  • 72. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Eye diagrams (old Sights only) Eye diagrams are obtained by superimposing all the time frames of a bit sequence. This function is very useful to check jitter and intersymbol interference. Usually, this function requires the definition of stimulus signals with long bit-sequences. 398.00 399.00 400.00 401.00 402.00 403.00 404.00404.40 TIME[nS] -2.00 V -1.75 V -1.50 V -1.25 V -1.00 V -0.75 V -0.50 V V(116) Looking at simulation results 12-6
  • 73. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Other useful functionalities of SIGHTS (Old Unix version only)• Multiplot Plots each waveform in a dedicated section of the graphic window • Scanplot Plots sequentially all the waveforms of the graphic file net by net • XY Plot Can use the samples of a waveform as X-axis • Waveform cursors Displays the numeric values of the waveform through a couple of cursors • Zoom Enlarges sections of the graphic window • Piece-Wise Linear (PWL) extraction A set of selected samples can be extracted from a waveform and saved on a PWL file • Measurement instrument interfaces Allows the acquisition of measured waveforms (DSO, TDR) to be compared with simulations or used to build up behavioral models through PWL extraction. • Mathematical functions All typical mathematical operations can be performed on waveform samples Looking at simulation results 12-7
  • 74. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Output waveform postprocessor 13-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 75. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Output waveform postprocessor (1) Overshoots, undershoots, rise and fall times can be extracted from the graphical output file Design: xxxxxxxx Number of samples: 1000 Time Step: 2.6e-10 -------------------------------------------------------------------------------- Net: /A(1) Class: defaultcmos Part Pin Rise Fall Rising Rising Falling Falling Time Time Edge Edge Edge Edge Ovsh Udsh Ovsh Udsh (ns) (ns) (V) (V) (V) (V) IC6 5 8.190 5.704 5.396 4.904 -0.459 0.402 IC9 9 8.219 5.675 5.417 4.850 -0.447 0.410 IC3 9 10.042 7.299 5.510 4.743 -0.436 0.452 IC6 9 8.141 5.637 5.407 4.897 -0.463 0.408 IC2 1 8.561 5.976 5.353 4.861 -0.431 0.419 -------------------------------------------------------------------------------- All the testpoints parameters can be displayed or filtered in order to store only the testpoints that violate the user- defined value. Output waveform postprocessor 13-2
  • 76. PRESTO 3.2 Training Course Version 1.0 HDT proprietary 1) Run the simulation with graphic output as option 2) Set the parameters in the Wave postprocessor window 3) Click on Run 4) View result Output waveform postprocessor (2) Output waveform postprocessor 13-3
  • 77. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Pin-to-Pin delay • Activated by View->Delay Report • Evaluates the propagation delay between the driver and the receivers. • Four values are given: two for the rise edge and two for fall edge. • For each edge the maximum/minimum delay are evaluated (related to Vil and Vih threshold crossing) 13-4 Vil Vih VOmin VOmax Threshold unloaded driver loaded driver receiver tdd tdmin tdmax tdm driver stimulus
  • 78. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Simulating crosstalk 14-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 79. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Simulating crosstalk • Check for noise between two or more parallel traces (coupled lines) • Coupled lines can belong to different layers • Crosstalk simulation can be added to SSN analysis • Compliance checks can be performed on signals affected by crosstalk noise • Losses can be taken into account Simulating crosstalk 14-2
  • 80. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Crosstalk analysis flow 1 2 3 10 20 30 1 2 3 10 20 30 1 2 3 10 20 30 unbalanced TL balanced TL 1 2 20 t t t • Coupled structures are identified scanning the design using geometrical filters specified by the user • Coupled structures are composed by parallel traces with any orientation. • Up to 32 parallel traces can be simulated for each layer. Up to 4 layers (between two metal planes) can be taken into account simultaneously. • The EM field solver (PREFIS) evaluates the coupling parameters. • A transmission line model based on Marx method (striplines) or modal method (microstrips) is created and included in the netlist. • The victim net is selected. • The simulation is performed Simulating crosstalk 14-3
  • 81. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Extracting coupled structures • Coupled structures are extracted by means of an exhaustive geometrical analysis of the routing. Three parameters can be specified: – mininum length: specifies the minimum length of a coupled segment to consider during the search – maximum distance: specifies the maximum distance between two parallel segments to consider during the search – resolution: is the minimum length of a coupled section to be considered significant during a crosstalk simulation Simulating crosstalk 14-4
  • 82. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Crosstalk structures Min Length = 50 mm MaxDistance = 2 mm Resolution = 5 mm PARAMETERS SETUP: 8015 20 4 4 Net 5 Net 1Net 2 Net 3 Net 4 xtk1xtk2 xtk3 Primary structure (length > Min Length) Secondary structure (length < Min Length length > Resolution) Discarded structure (lenght < Resolution) • A primary structure is a coupled section of length > Min Length. • A secondary structure is a coupled section of length < Min Length that is the continuation of a primary structure or other secondary structures. • All secondary structures of length < Resolution are discarded. • A structure can be neglected be the user (Action->Delete Xtalk) Simulating crosstalk 14-5
  • 83. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Victim nets • Optionally, during the analysis, a selected net (victim net) is held at quiet state while the others (disturbing nets) switches. This can be specified for each structure of the list in two ways: – one by one manually – automatically by the program (the selected net is in the middle of the structure) • The quiet state can be a logic “0” or “1” depending on the net class assigned to the victim net. victim net selection. NONE selection means no victim net (to be used for differential pairs) net class assigned to the victim net (NONE for differential pairs Simulating crosstalk 14-6
  • 84. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Electromagnetic Field Solver • The PRESTO electromagnetic field solver (PREFIS) utilizes the method of moments and returns the LC matrices of the coupled structures. • Each Stripline structure (with homogeneous dielectric) is then converted in a transmission line equivalent subcircuit by means of the Marx method. • Each Microstrip structure is then converted in an equivalent subcircuit by means of the multimodal decomposition. • The structures analyzed are stored in a special database (one for each design) and are available for further simulations to skip further calculations. Simulating crosstalk 14-7
  • 85. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Running crosstalk analysis • Run the Crosstalk Preprocessor with the specified geometrical filters • Choose the victim nets and assign net classes to them (optional) • Set Xtalk analysis button in Setup Simulation menu • Run the simulation Simulating crosstalk 14-8 Note: the user is allowed to not assign the victims during the crosstalk analysis. In this case the models of the interconnections will take in to account the crosstalk, but all the signals will be switching. This can be useful, for example, when a couple of balanced differential lines are analyzed.
  • 86. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Crosstalk analysis results • Results can be obtained in ASCII or graphical way, according to the setup of the simulation setup menu – if the setup is ASCII: the results are available in the .rep file as masks violation reports – if the setup is graphical: the results can be displayed with SIGHTS as waveforms t Simulating crosstalk 14-9
  • 87. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Simulating SSN 15-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 88. PRESTO 3.2 Training Course Version 1.0 HDT proprietary SSN analysis • Check for noise caused by drivers switching simultaneously. • Noise affects both drivers held at quiet state and receivers thresholds. • SSN macromodels are automatically built up by means of the physical model descriptions. • SSN analysis is fully compatible with crosstalk checks. SimulatingSimulating SSN 15-2
  • 89. PRESTO 3.2 Training Course Version 1.0 HDT proprietary SSN analysis flow t t t • SSN macromodels of ICs are built up automatically starting from library model description. • A common package model is automatically inserted into the IC model. (RLC, Transmission Line or S-parameters models are allowed) • Switching drivers are connected to their actual interconnection topologies. • Quiet drivers are set to “0” or “1” logic level. • The noise caused by the switching outputs affects also the behavior of the clamping diodes of receivers belonging to the same package. • Clamping diode currents of receivers affect the behavior of other drivers/receivers belonging to the same package. 1 2 3456 7 8 9 FILE_TYPE=HDT_PLIB; TIME=Thu Dec 10 10:45:33 1992 COMPONENT=AC04, 74AC04; FAMILY=FACT; PACKAGE=DEFAULT, DIP14, SOIC14; FACTORY=DEFAULT; TYPE=IC; NPINS=14; BEGIN_PIN FACT_DR24_P=2,4,6,8,10,12; FACT_RC_P=1,3,5,9,11,13; FACT_GND_P=7; FACT_VCC_P=14; END_PIN; BEGIN_FUNCTION DRIVER=2,4,6,8,10,12; RECEIVER=1,3,5,9,11,13; POWER_FACT=14; GROUND_FACT=7; END_FUNCTION; END. gnd1 package pins power1 package pins power2 package pins input output on-chip power1 net on-chip gnd1 net on-chip power2 net on-chip gnd2 net gnd2 package pins ... ... ...... supply pin models supply pin models modelsmodels Simulating SSN 15-3
  • 90. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Percentage of switching drivers (1) How many drivers switch simultaneously for each component? This number is usually very difficult to set in case of large components: • for simple components (e.g. AC244) the assumption is very easy: the worst case is obtained with all drivers switching except one that is set at quiet state. • for complex components having, for example, more than one output bus, the actual timing of the design becomes very important and the percentage of switching drivers is different for each component. Normally, the previous rule (all drivers are switching except one) cannot be applied, because the number of power pins of large components is usually not designed on the basis of all driver switching assumption: This hypothesis can be too pessimistic. Simulating SSN 15-4
  • 91. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Percentage of switching drivers (2) PRESTO allows two approaches: a) rough simulation: a fixed percentage of switching drivers is assigned to component packages b) accurate simulation: 1) select a time window on a logic simulation already performed on the design. 2) utilize the bit sequences obtained as output of the logic simulation to set PRESTO signal stimuli and related net classes. 3) assign the classes to the nets 4) simulate a Real Timing Simulation: the percentage of switching drivers will be the real one. Note: automatic interfaces between your logic simulator and PRESTO can be easily implemented. Contact HDT for more information about Real Timing Simulation Simulating SSN 15-5
  • 92. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Running SSN analysis • Set SSN button in the Simulation Setup window • Set the SSN parameters: percentage of switching drivers (100% in case of Real Timing Simulation) and quiet state net class • Run the simulation Simulating SSN 15-6
  • 93. PRESTO 3.2 Training Course Version 1.0 HDT proprietary SSN report • The drivers to be set quiet are automatically chosen by the system in a random way. The report file (.brep) reports the configuration utilized for the simulation. *** Simultaneous Switching Noise Report *** Design name: xxxxxxx -------------------------------------------------------------------------------- Pin name Net name Status Class -------------------------------------------------------------------------------- Instance IC21 Component 74AC04 package DIP14 factory DEFAULT 2 /A(1) ACTIVE defaultcmos 4 /A(2) ACTIVE defaultcmos 6 /A(3) ACTIVE defaultcmos 8 /A(4) ACTIVE defaultcmos 10 /A(5) ACTIVE defaultcmos 12 /A(6) VICTIM defaultgnd -------------------------------------------------------------------------------- ... ... Switching nets: net classes are set by means of the Net Editor window . Quiet net: net class is a parameter of the SSN setup and overrides the net class assigned by means of the Net Editor window during the SSN analysis. Simulating SSN 15-7
  • 94. PRESTO 3.2 Training Course Version 1.0 HDT proprietary SSN results • Results can be obtained in ASCII or graphical way, according to the setup of the simulation setup menu – if the setup is ASCII: the results are available in the .rep file as masks violation reports – if the setup is graphical: the results can be displayed with SIGHTS as waveforms t Simulating SSN 15-8
  • 95. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Physical library 16-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 96. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Physical library • Contains the physical model descriptions. • Data base organized. • Component creation and library management fully supported by the PRESTO graphical interface. • Support different component pinout description associated to different package pinouts Note: a component can be available in different packages. The pinout of these can be different, so that more than one physical model can be required for the same component. PRESTO searches the component in the library data base using a key composed by the component and the package name, so that the model can be correctly identified. Physical library 16-2
  • 97. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Physical Model Describes: – the pinout of the component package – the function of the pin (driver, receiver, power supply, etc) – the name of the electrical model to utilize during the simulation 1 2 3 4 5 6 7 8 9 FILE_TYPE=HDT_PLIB; TIME=Thu Dec 10 10:45:33 1992 COMPONENT=AC04, 74AC04; FAMILY=FACT; PACKAGE SOIC14; FACTORY=DEFAULT; TYPE=IC; NPINS=14; BEGIN_PIN FACT_DR24=2,4,6,8,10,12; FACT_RC=1,3,5,9,11,13; FACT_GND=7; FACT_VCC=14; END_PIN; BEGIN_FUNCTION DRIVER=2,4,6,8,10,12; RECEIVER=1,3,5,9,11,13; POWER_FACT=14; GROUND_FACT=7; END_FUNCTION; END. Physical library 16-3
  • 98. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Physical model types • Resistors, capacitors, inductors, diodes • Integrated circuits • Programmable logic devices • Connectors • Special components Physical library 16-4
  • 99. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Physical model definition The model description is done by means of the Physical Model Editor window. The resulting description can be saved directly in the physical library or exported in a file having the Physical Model Description format (ASCII file with .pmd extension) Model parameters (library, component name, pin number and packages list) Model description Physical library 16-5
  • 100. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Physical Model Description format (PMD) FILE_TYPE=HDT_PLIB; TIME= xxxxxxxxxx COMPONENT=component_name; FAMILY=xxxxxxxx; PACKAGE=xxx; FACTORY=DEFAULT; TYPE=xxxxx; NPINS=nn; BEGIN_PIN model_name=pin_list; END_PIN; BEGIN_FUNCTION function_name=pin_list; END_FUNCTION; BEGIN_POWER power_name=pin_list; END_POWER BEGIN_CLASS net_class_name=pin_list; END_CLASS; BEGIN_DR_LIST driver_list; END_DR_LIST; BEGIN_VSET voltage_value=pin_list; END_VSET; END. Header pin to electrical_model assignment pin function (Driver, Receiver, Bidirectional, etc) pin to power pin association: describes which power/ground pin powers the other functions (driver, receiver, etc) pins default net class to pin assignment (not mandatory) driver list (only if bidirectional, 3-state or open collector functions are present in the model) power supply voltage assignment (connectors only) Physical library 16-6
  • 101. PRESTO 3.2 Training Course Version 1.0 HDT proprietary R,L,C, Diodes • These are two-pin models • Only one electrical model can be associated to the physical models 1 RECEIVER myresistor 2 RECEIVER myresistor RES DEFAULT R 2 RES is the name of the physical component Default is the package type for which the model applies “R” is the TYPE that applies for resistors The description requires the pin name, the function (always RECEIVER for these components) and the name of the electrical model (myresistor in this case). Physical library 16-7
  • 102. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Integrated circuits • One electrical model has to be assigned to each pin of the component functioning as DRIVER or RECEIVER. • Two electrical models have to be assigned to each pin functioning as BIDIR, 3STATE, OPCOL (one driver and one receiver models). • An electrical model must be assigned to each pin functioning as POWER. This model is utilized during the analysis of the special nets (power and ground nets) behavior. Physical library 16-8
  • 103. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Example of IC description 1 RECEIVER ac_rc vcc gnd 2 RECEIVER ac_rct vcc gnd 3 DRIVER ac_dr8 vcc gnd 4 BIDIR ac_bd8 ac_rc vcc gnd 5 POWER vcc_mod vcc 6 POWER gnd_mod gnd 7 POWER gnd_mod gnd 8 ... 9 ... MYIC DIP14 IC 14 pin 1 has function RECEIVER, the electrical model to utilize is “ac_rc” and the power pins of the electrical model must be powered through the pins 5 and 6 (the package model will be automatically connected). pin 3 has function DRIVER and the electrical model to utilize is “ac_dr8” (8mA driver in this case). pin 4 is bidirectional, so two electrical models must be specified: one will be used when pin 4 acts as DRIVER and the other one when the pin acts as RECEIVER. pins 5 and 6 are power and ground pins. They have a power electrical model associated and a power name (vcc for pin 5 and gnd for pin 6 in this case) 1 2 3 4 5 6 7 8 9 1 0 1 1 1 2 1 3 1 4 v c c g n d (the package model is not shown) Physical library 16-9
  • 104. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Programmable Logic Devices (PLD) • Their I/O description is not fixed but design dependent (driver and receiver configuration is programmable). • The same design can contain more than one PLD device having identical part name but different pin configuration (a different instance name of course) • The description is similar to IC description but the component name must contain the design and the instance name with a special syntax. part_name@instance_name@design_name ex: IDTxxx@IC21@MYDES Only the first 5 characters of the design name are necessary. Physical library 16-10
  • 105. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Connectors (CON) • Like PLD, the connector configuration is design dependent • While the previous models describe the drivers and receivers inside the design, connector models allow the description of drivers and receivers outside the design and their interconnection to the circuitry inside the design under test. • If the external connections are known, connector models allow you to accurately simulate also the behavior of the interface interconnections. • If the external connections are unknown, the description of this model can be avoided using the Default Models Physical library 16-11
  • 106. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Connectors (2) • Specific electrical models can be utilized to take into account the actual external interconnections of driver/receiver. design under test connector physical model standard driver or receiver Special driver or receiver with its actual interconnection description (RLC, TLM, behavioral, ...) Physical library 16-12
  • 107. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Connectors (3) • The component name of connectors is specified like that of PLD devices (design-dependent components) part_name@instance_name@design_name e.g.: CONN5PIN@IP21@MYDES Only the first 5 characters of the design name are required. • One additional section of the description is utilized to specify the power and ground supply of driver/receivers models. In this way, it is also possible to simulate ground voltage shift between the design under test and the external circuitry and its effects on signal integrity. Physical library 16-13
  • 108. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Example of connector model 1 RECEIVER ac_rc 5 0 2 RECEIVER ac_rct 5 0 3 DRIVER ac_dr8 5 0.2 4 BIDIR ac_bd8 ac_rc 5.2 0 5 GENPOWER vee -4.5 6 GENPOWER gnd 0.0 7 ... 8 ... 9 ... CON15@J1@TUTOR CONN15PIN CON 15 pin 1 is connected to a RECEIVER, the electrical model to utilize is “ac_rc” and its power pins are connected to a 5/0V power supply. pin 3 is connected to a DRIVER and the electrical model to utilize is “ac_dr8” (8mA driver in this case). The power pins are connected to a 5/0.2 power supply pin 4 is bidirectional, so two electrical models have to be specified: one will be used when pin 4 acts as DRIVER and the other one when the pin acts as a RECEIVER. pins 5 and 6 are power and ground supply pins (GENPOWER function). They have a power supply electrical model associated and a supply voltage. 1 2 3 4 5 1 5 - 4 . 5 V p o w e r n e t d e s i g n u n d e r t e s t e x t e r n a l w o r l d c o n n e c t o r g r o u n d n e t0 V 6 5 V 0 V 5 V 5 V 5 . 2 V 0 V 0 V 0 . 2 V Vset+ Vset- Physical library 16-14
  • 109. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Special components • These models describe the component as a black box, and their internal structure is described by a SPRINT netlist without explicit driver/receiver declaration. The number of pins of the physical description must match that of the related electrical model. • SC modeling allows wide flexibility in modeling of the internal functionality of the device. For example, it is possible to build up models taking into account logic and timing behavior of the core of the device (see Electrical library section). Physical library 16-15
  • 110. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Library management • To insert a model in library: – Create a model description. – Choose Save in Library specifying: » the target library » the component name » the package name – If the library doesn’t already exist, a new one will be created. • To extract a model from library: – Choose Load Component Data specifying: » the target library » the component name » the package name – The model will be then displayed in the Model Editor window. Physical library 16-16
  • 111. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Importing and exporting models • To import a model from an ASCII file (PMD syntax): – Select the Import command and specify the file to load. – The model description will be loaded in the Component Editor window. • To write a model on an ASCII file (PMD syntax): – Select the Export command and specify the output file name. – The model description will be saved on the specified file. 16-17 Physical library
  • 112. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline Electrical library 17-1 • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
  • 113. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Electrical library • Contains the electrical model descriptions (driver, receiver, passive components, etc). • It is organized as a data base. • Library management is fully supported by the PRESTO graphical interface. • Model architecture is fully user-definable • Models are MODENV compatible Electrical library 17-2
  • 114. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Modeling capabilities • The models are described as .SUBCKT circuits in SPRINT syntax. • The model architecture is user-definable. • A set of default architectures is available for typical situations. • All SPRINT primitives can be utilized within the model and in particular: – resistors, inductors, capacitors; – non linear resistors – time/voltage/current controlled resistors (switches) – independent or voltage/current dependent sources – dynamic or static transfer functions – transmission lines – time domain scattering parameters (including measure-based data). • PRESTO allows the definition of hierarchical modeling (max. two nesting levels). Electrical library 17-3
  • 115. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Model types • Driver/Receiver – 4-pin models – Suitable for ICs/PLDs/CONNECTORS I/O descriptions – Selectable package • R,L,C,Diodes, nonlinear resistors, voltage generators – 2-pin models – Suitable to model 2-pin passive components, IC power pins (to simulate the behavior of supply nets, voltage power supply, etc) • Special Components (SC) – n-pin (n >= 1) models. – utilized to model the behavior of a whole device, for example a resistive array or an operational amplifier. – allows the creation of complete electrical/logic/timing descriptions of simple components. Electrical library 17-4
  • 116. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Receiver Model sources, passive elem., measures, power node ground node input node at "analog" "logic" levels "0" and "1" 0 1 output node atelectrical levels"V1" "V2" V2 V1 etc Input pin is automatically connected to its external net and acts as an electrical load Output pin provides a digital signal (0 1) obtained by an internal threshold Power and ground pins are automatically connected to the power and ground nets supplying the device.component power rail ground rail Electrical library 17-5 package
  • 117. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Example of simple CMOS receiver model in out vcc gnd Cin STF Pvcc Pgnd 1 2 10 20 E1 .SUBCKT name 1 2 10 20 CIN 1 0 value PVCC 1 10 vcc_static_char C=1P PGND 1 20 gnd_static_char C=1P E1 2 0 1 20 THR( 2.5 0 1 ) .ENDS name name is the name identifying the electrical model in the Sprint netlist, value is the value of the input capacitance, vcc_static_char is the static characteristic of the vcc clamping diode and gnd_static_char is the static characteristic of the gnd clamping diode. Usually, the static characteristic of the diode is expressed as a Piece Wise Linear fitting of its actual V,I characteristic. Electrical library 17-6
  • 118. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Driver model sources, passive elem., measures, power node ground node input node at "logic" levels "0" and "1" 0 1 output node at "analog" electrical levels"V1" "V2" V2 V1 etc. component power rail ground rail Output pin is connected to its net and acts as a generator Power and ground pins are automatically connected to the power and ground nets supplying the device. Input pin is used by Presto to connect the driver to a digital stimulus (0-1 levels) that defines the switching sequence Electrical library 17-7 package
  • 119. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Example of CMOS driver model out vcc gnd Cout 2 10 20 Pvcc Vcomp E1 RSWvcc + + Pgnd RSWgnd + E0 Td STF STF DTF DTF 1 in SUBCKT name 1 2 10 20 COUT 2 0 value RSWVCC 7 2 1 0 PWL(0V 1E6 1V 0 2V 0) C=2P PVCC 7 8 1_static_char C=2P E1 8 9 1 0 dtf stf 0.1NS VCOMP 10 9 DC(5) RSWGND 17 2 1 0 PWL(-1V 0 0V 0 1V 1E6) C=2P PGND 17 18 0_static_char C=2P E0 18 19 1 0 dtf stf 0.1NS TD 19 20 C=6P .ENDS name name is the name of the electrical model within the Sprint netlist, value is the value of the output capacitance, 1_static_char is the static characteristic of the output at "1" logic level, 0_static_char is the static characteristic of the output at "0" logic level, stf is the static transfer function of the output and dtf is the dynamic transfer function of the output. Electrical library 17-8
  • 120. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Special components component power rail ground rail core Any Sprint netlist using any Sprint primitive 1 3 5 7 n -1 2 4 6 8 n • PRESTO doesn’t provide automatic driver/receiver management for SC • The internal description has to be complete and the output signals (to the external nets) depend only by the input signals (coming from the external nets) or by signal generated internally by means of user-defined voltage/current sources • Allows the modeling of crosstalk between pins belonging the same package Electrical library 17-9 package
  • 121. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Example of special component model AC02 (four NOR): 1234567 gnd vcc standard receiver model 8 9 10 11 12 13 14 R 1V 0V Delay Delay Delay 2 3 1 Single NOR model Four NOR models A B OUT 0 0 1 1 0 0 0 1 0 1 1 0 standard driver model pin crosstalk model Electrical library 17-10 . .. timing/logic core
  • 122. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Importing and exporting models • To import a model from an ASCII file (SPRINT syntax): – Select a target library. – Select the Import command and specify the file to load. – The model description will be loaded in the target library. • To write a model on an ASCII file (SPRINT syntax): – Select a source library – Select a model from the list displayed in the window – Select the Export command and specify the output file name. – The model description will be saved on the file. Electrical library 17-11
  • 123. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 18-1 Layout optimisation
  • 124. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Performing a “What-If?” analysis • Check the effects of small modifications of the design: “What happens if I try to … ?” • Action at component level: – deleting or changing the values of existing components – inserting new components (e.g. decoupling capacitors, matching resistors, noise sources) • Action at layout level: – deleting existing segments – adding “physical” segments (with electrical properties defined by their geometry) – adding “electrical” segments (with electrical properties set up by the user) Layout optimisation 18-2
  • 125. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Friendly Graphic User Interface Layout optimisation 18-3 Click with the center button of the mouse on a layout object (net, pin, via) to identify it Select What-If analysis to open the optimisation window: it’s necessary to choose if dealing with Components or with Segments
  • 126. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Component optimisation Layout optimisation 18-4 Currently deleted/ insereted/ modified components. They are identified by: • Component name (it’s the name of the physical component as found in the library) • Package name and Factory name • Instance name • Value (for passive component only) • Type Modification token “Enable/Disable”: this allows to perform multiple simulation with or without some modifications in order to point out the best solution Component properties and pin connection window
  • 127. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Segment Optimisation Electrical Segment insertion window Currently deleted/ insereted/ modified segments. Their related net is displayed Physical Segment insertion window 18-5 Layout optimisation
  • 128. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Training course outline • PRESTO important concepts • CAD data extraction • PRESTO input format • Library Setup • Special Nets • Aliases setup • Signal stimuli creation • Signal mask creation • Net class definition • Simulation setup • Running simulation • Looking at simulation results • Output waveform postprocessor • Simulating crosstalk • Simulating Simultaneous Switching Noise (SSN) • Physical library • Electrical library • Performing What-If analysis (layout optimisation) • Performing EMI analysis 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 19-1 EMI analysis
  • 129. PRESTO 3.2 Training Course Version 1.0 HDT proprietary EmiR analysis flow EMI analysis A Signal Integrity simulation with suitable stimuli is performed A Fast Fourier Transform of the currents flowing through the traces allows the simulator to work in the frequency domain An analytical method based on the Green dyadic is used to evaluate the field radiated by the traces 19-2
  • 130. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Time domain parameters setup The simulation time window is completely defined by the frequency parameters of EmiR: • Tstart is 100ns, because the analysis in the time domain must be “transient-free” • Minimum working frequency: this affects the Tstop parameter, because the FFT must be performed on a complete period of the signal • Maximum working frequency: this affects the resolution parameter, because the FFT algorithm must have enough sampled data to provide high frequency results • Simulation Time Step: the user can modify this parameter, but a check is performed and an error message is displayed if it’s too large compared to the selected frequency domain 19-3 EMI analysis
  • 131. PRESTO 3.2 Training Course Version 1.0 HDT proprietary EMI simulation characteristic • The Cross Talk analysis is not compatible with the EMI one • Defined stimuli and delay are neglected (all the nets are driven with a 50% duty cycle waveform selected according to the minimum EMI frequency), then: – the analysis is made at only one digital frequency – all the nets have signals “in phase” – the even harmonics of the spectrum are very lower then the odd ones (this depends on the 50% duty cycle) 19-4 EMI analysis
  • 132. PRESTO 3.2 Training Course Version 1.0 HDT proprietary EmiR setup Anechoic chamber analysis Run EmiR analysis Semi-anechoic chamber analysis Near Field analysis Far Field analysis H-Field spectrum EMI Maps Radiation Diagram E-Field Spectrum Far Field from the board Far Field from the board with an attached cable EMI ProfilesE-Field Spectrum 19-5 EMI analysis
  • 133. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Anechoic chamber analysis Select low frequency algorithm Provide all field components: (Ex, Ey, Ez) Select results in Root Mean Square dBuV/m Select frequency for radiation diagram 19-6 EMI analysis
  • 134. PRESTO 3.2 Training Course Version 1.0 HDT proprietary Semi-anechoic chamber analysis Use a fixed height for the antenna or perform a scan, taking as results the maximum field calculated at each step Define cable parameters. NOTE: it is supposed to be solded at the ground plane of the board 19-7 EMI analysis

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