A 1.25Gb/s high gain, wide dynamic range pre-amplifier in 0.35 H5; m CMOS

This paper presents a 1.25Gb/s high gain optical receiver pre-amplifier featuring a wide dynamic range in 0.35μm standard CMOS. The designed amplifier is configured on three identical stages, incorporating the automatic gain control (AGC) technique to achieve a wide input dynamic range and a good noise performance. The post-simulations demonstrate the transimpedance gain of 80.5dBΩ, the -3dB bandwidth of 950MHz for 0.5pF photodiode capacitance, the average noise current spectral density of 6.4pA/√Hz, a maximum input current of 2.5mA, and the DC power dissipation of 77.9mW from a single 3.3V supply. The chip area is 0.582×0.510 mm².