Abstract: | High-bit-rate optical communication links require high performance circuits. Electrical time division multiplex (ETDM) single channel bit-rate of 40 Gb/s is at hand, due to recent progress in both technology and design methodology. Multilevel modulation format can be envisaged for ETDM transmission. An InP double heterojunction bipolar transistor technology is presented in this paper. The methodology used and tools developed with optical communications in mind are also discussed. Fabricated circuits are reported: 40 Gb/s multiplexer and demultiplexer, a 20 Gb/s driver, a 30 Gb/s selector-driver, a 22 Gb/s decision circuit, and a decision-decoding circuit for multilevel transmissions |