GENERALMODELFORDELAYEDFEEDBACKANDITSAPPLICATION TO TRANSIMPEDANCE AMPLIFIER'S BANDWIDTHOPTIMIZATION
Eliseu A. L. Macedo · 2006
Delays inrealsystems canbeoftwotypes: i)intrinsic R(S) delays -duetothephysical principles ofoperation ofeach electronic device; ii) designed delays -duetoextra circuits ) usedtoaddthedesired delay. Previous workestablished the possibility ofachieving bandwidth improvements using smalldelays inside thefeedback loopoffeedback : A:)A(s) amplifiers. Themodeling approach followed onthese contributions usedonlyonedesigned delay element. The bandwidth reduction effect duetointrinsic delays wasnot b considered onthese contributions. Thispaper extends the Figure 1-Circuit design concept concept tothegeneral caseoffeedback amplifiers that modeling [5]). Theintroduction ofthedesigned delay incorporates delays ofbothtypes. element further extends thepotentialities oftheproposed An experimental demonstration using a simple 0.35fi m model. Anoptimized transimpedance amplifier, suited to BiGMOStransimpedance amplifier further confirms the optical receivers withlarge area photodiodes (l5OpF), was proposed model. designed toevaluate this model.