A 10.5 Gb/s transimpedance amplifier using capacitive emitter degeneration technique

A 10.5 Gb/s modified shunt-feedback transimpedance amplifier in a commercial 0.35 μm SiGe BiCMOS technology is presented. A capacitive emitter degeneration technique was used to improve the bandwidth performance of the transimpedance amplifier. It achieved a transimpedance gain of 56 dB Ω, a −3 dB bandwidth of 6.2 GHz with a 0.4 pF input parasitic capacitance value, and a noise current spectral density of 9.46pA/Hz. The total circuit dissipates 29 mW under a 3.3 V supply, and the chip size is only 0.25 × 0.165 mm2.