0.2 μm GaAs PHEMT distributed amplifier for 40 Gb/s optical receiver

A preamplifier designed for a 40 Gb/s optical receiver was developed by using 0.2 μm GaAs PHEMT (pseudomorphic high electron mobility transistor) technology. A seven-unit distributed amplification structure with the active bias is employed for the preamplifier, where the 3 dB bandwidth is beyond 40 GHz, the return loss of either input or output end is less than -10 dB, the transimpedance gain is approximately 45.6 dBΩ, the minimum equivalent input noise current density is 22 pA/√Hz, and the total power consumption is 300 mW. All results show it is suitable for a 40 Gb/s optical receiver.