ABSTRACT Advanced Simulation and Modeling for Electronic System Hardware Design 1 of 52
Advanced Simulation and Modeling for Telecom System Hardware Design 2 of 52
Outline X Requirements for simulation tools X PRESTO: New software to met these needs X Measurements-based modeling X Modeling specifics for many kinds of devices X Detailed case study: Point-to-point ATM Interconnect X Other telecommunications applications 3 of 52
Digital Communications’ Design Process Hardware/Software Integration & Test System Verification & Debugging Functional Conformance Verification Early Production Test System & Mnfg Process Verification & Debugging Process Architecture Low-level Code Debug Unit test Optimisation Test System Design Comp. Source & Evaluation PCB Design * ASIC/ FPGA Design System Design * Component design NIC, Fabric & CPU Prototype Turn-on System Analysis & DesignManufacturing Process Design Tool Selection Architectural Design Investigation Hardware Design Application Code Debug Unit test Optimisation To Manufacturing, Field Trials and Conformance Labs Mfng Process Design 4 of 52
The Need for Advanced Tools X Modern communications systems present new challenges in speed and complexity SONET/SDH (155 MOPS to 2.4 GBPS) Switching Systems for B- ISDN Þ STM crossconnects Þ ATM switches Þ High-speed LANs Þ GSM Y Technology advances complicate the difficulty Þ High-density component technology Þ Very fast edge rates in components Þ Large-scale system Integration 5 of 52
Requirements of These Tools Y Simulate large systems Y Handle signal integrity effects Y Very fast; to enable “what-if” analyses. Y Model all system components. Y Derive models from various sources. Þ Vendor data/ IBIS models Þ EM field solvers Þ Spice analysis Þ Measurements of actual devices Y Provide accurate results. 6 of 52
Comparison With Conventional Simulation Tools Y Spice-based simulation Very good driver/receiver models Reliable and familiar In widespread use Difficult to simulate large systems. l Slow, especially with T-lines & inductors. l Convergence problems l Limited problem size Limitations of modeling Analysis often net-by-net. 7 of 52
Comparison With Conventional Simulation Tools Y Special signal integrity analysis analyzers; behavioral models Fast, compared to Spice. Specialized for transmission line analysis. They do rarely a real simulation; use formulas instead. Models often of limited accuracy. 8 of 52
PRESTO Advanced Simulation & Modeling for Telecom Systems SIP IC decoupling GND VCC net coupled section via GND plane receivers drivers receiver 9 of 52
PRESTO Example : STM1 Crossconnect Simulation Versus Measurement 10 of 52
PRESTO Capabilities Y Has the speed and capacity to be an effective tool for design and validation of modern telecom systems. Y Shows all signal integrity effects. Y Can model all needed components. Ý Vendors data sheet models Ý Measurement-based models Y Provides accurate results: proven by measurements. 11 of 52
SPRINT: Fast, Full-system Simulation Y PRESTO includes the SPRINT simulator. Y SPRINT is very fast & can handle large problems. Y It uses unique digital wave, DSP-based algorithm. Ý Simulation time increases linearly with complexity. Ý Uses fixed time step. Ý No convergence problems. Y It handles efficiently inductors and transmission lines, R's, C’s, etc. Y It uses accurate, efficient behavioral models for drivers and receivers. 12 of 52
The Digital Wave Algorithm n SPRINT converts circuit to digital wave networks. n These are analyzed with fast DSP computational techniques n This method characterizes an element with the relationship of the incident and reflected waves. a = incident wave b = reflected Wave V=a+b I=(a+b)/Zo Wave Representation Digital Wave Network a b Z0Z0 Electrical Representation Electrical Network a b Z0Z0 GND v NI 13 of 52
BTM : A New Approach to Modeling 14 of 52
S-parameter Representation of Networks 15 of 52
2-Port DUT as BTM Black Box 16 of 52
Example of BTM Modeling: A Coaxial Cable 17 of 52
BTM: Modeling an Asymmetric Device 18 of 52
The Measurement Setup 19 of 52