40 Gb/s analog IC chipset for optical receiver using SiGe HBTs

A preamplifier with 35 GHz bandwidth and 48.7 dB/spl Omega/ transimpedance gain, an automatic-gain-control (AGC) amplifier core with 31 GHz bandwidth, and a 40 Gb/s decision circuit are presented for future optical-transmission systems at a data rate of 40 Gb/s in global communication systems. A self-aligned selective-epitaxial SiGe-base heterojunction bipolar transistor is used to implement these circuits. This analog IC chipset meets the requirements for a 40 Gb/s optical receiver.