A monolithic regenerative repeater circuit is described for T-1 type PCM transmission systems. The bipolar IC chip contains all the functional blocks and active components required for the regenerative repeater system, including the automatic line build-out (ALBO) circuitry. It offers significant performance, power reduction, and reliability advantages over conventional PCM repeater designs. This paper discusses the design approach and the system architecture of the monolithic repeater chip, and demonstrates some of the key performance features.