Design of wideband low noise transimpedance amplifiers for optical communications

Most optical communication receivers employ common-emitter (BJT) configuration for the transimpedance preamplifier. In this paper the common-base regulated cascode and common-emitter preamplifiers are compared in terms of low-noise and wide-band performances. The effect of capacitive and inductive peaking techniques on bandwidth and noise has been investigated for the two circuits. PSPICE simulations showed that both methods resulted in significant bandwidth extension for both circuits. The common-base preamplifier low input impedance resulted in more efficient use of the peaking methods by requiring lower capacitor and inductor values.