SpectreRF

Last updated February 23, 2019

SpectreRF is an option to the Spectre Circuit Simulator from Cadence Design Systems. It adds a series of analyses that are particularly useful for RF circuits to the basic capabilities of Spectre. SpectreRF was first released in 1996 and was notable for three reasons. First, it was arguably the first RF simulator in that it was the first to be designed for large bipolar and CMOS RF circuits; it used shooting methods as its base algorithm; and it pioneered the use of Krylov subspace methods.^[1] The use of shooting methods gave SpectreRF remarkable robustness and the Krylov methods gave it capacity that was roughly 100 times greater than existing simulators at the time.^[2] Previously such simulators were designed to simulate very small GaAs integrated circuits and hybrids. These simulators were based on harmonic balance and could reliably simulate circuits with tens of transistors whereas SpectreRF could simulate circuits with thousands of transistors.

Spectre is a SPICE-class circuit simulator. It provides the basic SPICE analyses and component models. It also supports the Verilog-A modeling language. Spectre comes in enhanced versions that also support RF simulation (SpectreRF) and mixed-signal simulation.

Cadence Design Systems American electronic design automation (EDA) software and engineering services company

Cadence Design Systems, Inc. is an American multinational electronic design automation (EDA) software and engineering services company, founded in 1988 by the merger of SDA Systems and ECAD, Inc. The company produces software, hardware and silicon structures for designing integrated circuits, systems on chips (SoCs) and printed circuit boards.

In linear algebra, the order-rKrylov subspace generated by an n-by-n matrix A and a vector b of dimension n is the linear subspace spanned by the images of b under the first r powers of A, that is,

SpectreRF added the Periodic Steady State and Periodic small-signal analyses to Spectre. The Periodic Steady-State or PSS analysis directly computed the periodic steady-state response of a circuit. The periodic small-signal analyses use the periodic steady-state solution as a periodically time-varying operating point and linearize the circuit about that operating point and then computes the response of the circuit to small perturbation sources.^[3] Effectively they build a periodically time-varying linear model of the circuit. This is significant as periodically time-varying linear models, unlike the time-invariant linear models used by the traditional small-signal analyses (AC and noise) exhibit frequency conversion. SpectreRF pioneered a variety of periodic small-signal analyses, including periodic AC (pac), periodic noise (pnoise), periodic transfer function (pxf), periodic s-parameter (psp) and periodic stability (pstb).

After its introduction, SpectreRF quickly became the dominant simulator for RF integrated circuits, and was instrumental in establishing Spectre as the most popular circuit simulator for integrated circuits. Eventually the dominance of SpectreRF faded as the use of Krylov subspace methods propagated to other simulators, particularly those based on harmonic balance. SpectreRF now provides harmonic balance in addition to shooting methods, both of which are accelerated using Krylov subspace methods.

SpectreRF was developed by Ken Kundert, Jacob White, and Ricardo Telichevesky.

Ken Kundert Creator of Spectre, SpectreRF, and Verilog-A. Pioneer of Analog Verification.

Kenneth S. Kundert is an engineer that is notable for his work in the area of Electronic Design Automation (EDA). He studied electrical engineering at the University of California, Berkeley under professors Alberto Sangiovanni-Vincentelli and Robert Meyer and received his doctorate in 1989. During this time he created the Spectre circuit simulator. He was elevated to the status of IEEE Fellow in 2007 for contributions to simulation and modeling of analog, RF, and mixed-signal circuits.

Jacob K. White is the Cecil H. Green Professor of Electrical Engineering and Computer Science at the Massachusetts Institute of Technology. He researches fast numerical algorithms for simulation, particularly the simulation of circuits. His work on the FASTCAP program for three-dimensional capacitance calculation and FASTHENRY, a program for three-dimensional inductance calculations, is highly cited. He has also done extensive work on steady-state simulation of analog and microwave circuits. White was a significant early contributor to the development of Spectre and SpectreRF.

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References

↑ Ricardo Telichevesky, Kenneth S. Kundert & Jacob K. White.Efficient Steady-State Analysis based on Matrix-Free Krylov-Subspace Methods. Proceedings of the 32nd Design Automation Conference, June 1995.
↑ Ken Kundert. Introduction to RF simulation and its application. Journal of Solid-State Circuits, vol. 34, no. 9, September 1999.
↑ Ricardo Telichevesky, Kenneth S. Kundert, Jacob K. White. Receiver characterization using periodic small-signal analysis. Proceedings of the 1996 IEEE Custom Integrated Circuits Conference, May 1996.

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[Telichevesky1995-1] Ricardo Telichevesky, Kenneth S. Kundert & Jacob K. White.Efficient Steady-State Analysis based on Matrix-Free Krylov-Subspace Methods. Proceedings of the 32nd Design Automation Conference, June 1995.

[Kundert1999-2] Ken Kundert. Introduction to RF simulation and its application. Journal of Solid-State Circuits, vol. 34, no. 9, September 1999.

[Telichevesky1996-3] Ricardo Telichevesky, Kenneth S. Kundert, Jacob K. White. Receiver characterization using periodic small-signal analysis. Proceedings of the 1996 IEEE Custom Integrated Circuits Conference, May 1996.