The Transimpedance Amplifier [A Circuit for All Seasons]

Many of today's communication systems incorporate a transimpedance amplifier (TIA). Although the TIA concept is as old as feedback amplifiers [1], it was in the late 1960s and early 1970s that TIAs found widespread usage in optical coupling and optical communication receivers. In a patent filed in 1967, Miller proposes the circuit shown in Figure 1 [2], which consists of two TIAs for converting a photodiode's current to a differential output voltage. Additionally, these amplifiers have become popular in radio-frequency (RF) receivers in the past 10 years [3]. This article deals with TIA design for optical and RF applications.