IBIS_HowToUse

linhowe

【文件名】:06617@52RD_IBIS_HowToUse.doc
【格　式】:doc
【大　小】:1074K
【简　介】:
【目　录】:
Introduction.................. 5
Scope..... 5
History and Motivation of IBIS Modeling. 5
Current State of IBIS Modeling. 6
Whither IBIS?...... 7
Symbolic Representation of an IBIS Device – Input Side 8
Symbolic Representation of an IBIS Model – Output Side........ 9
Model Types........ 9
Input....... 9
Output.... 9
I/O........ 10
3-state... 10
Open-drain............. 10
I/O_open_drain..... 10
Open_sink............. 10
I/O_open_sink....... 10
Open_source......... 10
I/O_open_source... 10
Input_ECL............. 11
Output_ECL.......... 11
I/O_ECL............. 11
3-state_ECL.......... 11
Terminator............. 11
V-I Data.. 11
Range of V-I Data 11
Measurement Conditions............. 11
Simulation From SPICE.. 11
The Four V-I Curves: Pullup, Power Clamp, Pulldown and Ground Clamp... 12
The IBIS Voltage Convention............. 12
Receiver Input Impedance and Matching 12
Driver Output Impedance and Matching 14
Waveforms at the Die vs. Waveforms at the Pins............. 15
Curves, Behavioral Models and Data Table Lookup Models.. 16
Examples of V-I Curves.. 16
Scaling V-I and Simulating the Results............. 19
V-T Data. 24
What Happens Electrically when a Buffer Switches?............. 24
C_comp 24
Buffer Delay.... 30
Ramp Data: Slew Rate............. 30
Scaling Slew Rate and Observing the Results in Simulation............. 31
V-T Curves.. 35
Advantages of V-T Curves: dV/dt Non-Linearity......... 35
Examples of V-T Curves.. 36
Inserting V-T Curve Non-Linearity and Observing the Results in Simulation............. 41
V-T Curves: a Real Example 45
Parasitics & Packaging 51
Pins, Connections, and Model Assignments........... 51
Package Parasitics............. 52
Pin Parasitics............. 52
Examples of Pin Parasitics............. 53
Simulation of Package Parasitics............. 53
Environmental Variables................ 56
Voltages, Temperatures, and Population Spreads. 56
Example: Drive Capability – “Worst-Case”........ 56
Can the Effects of Environmental Variables be Simulated?............. 60
Interactions Between the IBIS Model and Board Simulators................ 60
Introduction........... 60
SPICE Model Elements and SubCircuits............. 60
Time and Frequency............. 60
Time, Distance and Frequency: Lumped and Distributed Circuits: Transmission Lines 61
Transmission Line Equations............. 63
Transmission Lines, Reflection Diagrams, and the Bergeron Method. 64
Timing Simulations............. 64
Board Parameters............. 65
RLGC Matrices 65
Algorithms & Field Solvers.. 66
Vinl, Vinh, Vol & Voh............. 66
Switching Delay Times.... 67
Reflections, Crosstalk and Ground Bounce. 68
How to Tell if the Effect of C_comp is being Double-Counted..... 69
Noise Margin.. 70
Verifying Your Simulator and IBIS Model... 71
Rise and Fall Times, Slew Rates, V-T Curves and Verification............. 71
V-I Curves and Verification............. 80
Different Technologies: Different Models Really Do Give Different Results:. 83
Relation to High Frequency RF Analysis 89
EMI...... 89
General... 89
IBIS Syntax... 89
Advantages of the Data Lookup Model... 89
Data Monotonicity and Convergence......... 90
Examples: A Model IBIS Model File and Curves.. 90
Resources............. 91
References............. 91
Model Sources. 92
Modeling Oscilloscope Probes for Simulation Results.. 94
Model Accuracy, Precision and Verification........... 100
Why Do You Need to Know All This?........... 100
Summary: Design Guide.... 101
Methodology......... 101
What to do if You Don’t Have an IBIS Model to Simulate With.... 102
The Right Model for Each Design Phase and Design Challenge........... 102
The Minimum IBIS Specification......... 103
Adding Min & Max Worst Case Information........... 104
Adding More Connection and Parasitics Information........... 104
Adding V-I Curve Related Data.... 104
Adding V-T Curve Data.... 104