20 Gbit/s transimpedance preamplifier and modulator driver in SiGe bipolar technology

A transimpedance preamplifier and a modulator driver used in a 20 Gbit/s fibre-optic TDM transmission system are presented. The ICs were fabricated in an advanced SiGe bipolar technology. The amplifier is noted for its high gain (58 dBΩ) and low equivalent input noise current density (≃ 12 pA/√Hz) and the driver for its high output voltage swing (2.3 V single-ended, 4.6 V differential).