Design of a fully differential CMOS transimpedance preamplifier for 10 Gb/s optical receiver

A low cost and low power consumption optical receiver differential transimpedance preamplifier for 10 Gb/s high-speed optical communications application was presented. The preamplifier includes a tranimpedance amplifier(TIA), limiting amplifier(LA), and output buffer, the weak photo-current was amplified by the preamplifier to a differential voltage swing of 400 mVpp. The preamplifier was designed in 0.18 m CMOS technology. The receiver preamplifier circuit is with a transimpedance gain of up to 92 dB and -3 dB bandwidth of 7.9 GHz, which accommodates a photodiode capacitor of 250 fF. The noise simulation result shows that the average input-referred noise current spectral density is 23 pA/up to 8 GHz. The power dissipation of transimpedance amplifier, limiting amplifier and output buffer respectively drain is 28 mW, 80 mW, and 40 mW from the 1.8 V supply respectively. The chip size is 800 m1 700 m.