Sensitivity Analysis and Distortion Decomposition of Mildly Nonlinear Circuits

[摘要] Volterra Series (VS) is often used in the analysis of mildly nonlinear circuits. In this approach,nonlinear circuit analysis is converted into the analysis of a series of linear circuits. The mainbenefit of this approach is that linear circuit analysis is well established and direct frequencydomain analysis of a nonlinear circuit becomes possible.Sensitivity analysis is useful in comparing the quality of two designs and the evaluation ofgradient, Jacobian or Hessian matrices, in analog Computer Aided Design. This thesis presents, forthe first time, the sensitivity analysis of mildly nonlinear circuits in the frequency domain as anextension of the VS approach. To overcome efficiency limitation due to multiple mixing effects,Nonlinear Transfer Matrix (NTM) is introduced. It is the first explicit analytical representation ofthe complicated multiple mixing effects. The application of NTM in sensitivity analysis is capableof two orders of magnitude speedup.Per-element distortion decomposition determines the contribution towards the total distortionfrom an individual nonlinearity. It is useful in design optimization, symbolic simplification andnonlinear model reduction. In this thesis, a numerical distortion decomposition technique isintroduced which combines the insight of traditional symbolic analysis with the numericaladvantages of SPICE like simulators. The use of NTM leads to an efficient implementation. Theproposed method greatly extends the size of the circuit and the complexity of the transistor modelover what previous approaches could handle. For example, industry standard compact model, suchas BSIM3V3 [35] was used for the first time in distortion analysis. The decomposition can beachieved at device, transistor and block level, all with device level accuracy.The theories have been implemented in a computer program and validated on examples. Theproposed methods will leverage the performance of present VS based distortion analysis to the nextlevel.

[发布机构] University of Waterloo

[效力级别] Volterra Series

[关键词] RFIC;Volterra Series;Analog Circuits;Distortion Analysis;Sensitivity Analysis;Distortion Decomposition;Circuit CAD;LNA;Op-Amp;Electrical and Computer Engineering