Monolithic AGC loop for a 160 Mb/s transimpedance amplifier

A new BiCMOS monolithic automatic gain control (AGC) amplifier with wide dynamic range is described. The forward gain path has 120 k/spl Omega/ transimpedance, 140 MHz bandwidth, input noise current spectral density of 1.17 pA//spl radic/Hz and input signal current handling capability of 4 mA. An on-chip peak detector incorporating a 25 pA current source yields AGC hold times in the millisecond range.