The 1345-Type fiber-optic receiver is designed for use in transmission systems or medium- to highspeed data communication applications. Used in intermediate- and long-reach applications, the receiver operates at the SONET OC-3 or OC-12 data rate as well as the ITU-T synchronous digital hierarchy (SDH) rate of STM-1 or STM-4, depending on the receiver model chosen. The receiver meets all present Telcordia Technologies GR-253-CORE requirements, the current ANSI T1X1.5 intraoffice specifications, and the ITU-T G.957 and G.958 recommendations. Compact packaging, a high level of integration, and a wide dynamic range make these receivers ideal for data communications. Manufactured in a 20-pin DIP, the receiver consists of a planar InGaAs PIN photodetector, a silicon preamplifier, a silicon bipolar limiting amplifier that converts the small signal to ECL levels, a timing recovery unit to recover the clock, and a silicon bipolar decision circuit.