Monolithic ultra-broadband transimpedance amplifiers using AlGaAs/GaAs HBTs

Monolithic ultra-broad band transimpedance amplifiers have been developed using AlGaAs/GaAs HBTs (heterojunction bipolar transistors). The amplifiers have exhibited DC to 13.4-GHz bandwidth, with an 18.1-dB gain and a 49.8-dB Omega transimpedance. The standard deviations in gain and 3-dB roll-off bandwidth over 2-in wafers were as small as 0.42 dB and 0.47 GHz, respectively. These results have been brought about by optimized circuit design considering large signal operation and an affordable HBT fabrication process using a self-aligned method. Excellent 10 Gb/s NRZ (nonreturn to zero) pulse response has confirmed that the amplifiers are adapted to 10 Gb/s optical transmission systems.<
>