Design of a Novel CMOS Transimpedance Amplifier Based on a Current Mirror
Abstract
The transimpedance amplifier (TIA) is an essential component in optical communication systems. It converts the photodiode
current to a voltage for further processing. In this paper, a novel CMOS current-mirror-
based
TIA is proposed. Its suitability to
optical communication systems is verified. The current-mirror
topology is chosen due to its low input resistance and highly linear
current amplification. The proposed TIA employs negative feedback and shunt-inductive
peaking to extend the bandwidth.
Three configurations of the shunt-inductive
peaking are explored: one with passive inductors and two with active inductors. The
proposed TIA is verified by simulation using the 45-nm
CMOS technology with a 1-V
supply and 1-pF
photodiode capacitance
with the key performance trade-offs
discussed. A figure of merit (FoM) is introduced to evaluate the performance of the proposed
TIA. The simulation results of the proposed TIA with passive inductors show a gain of 30.6 dB, a 3-dB
bandwidth of 2.8 GHz, and
a power consumption of 1.63 mW, with an input-referred
noise current of 23.55 pA/√Hz.