An integrated interpolative PCM decoder

Discusses the technique of time averaging interpolation which provides a means for obtaining telephone quality digital-to-analog conversion using conventional digital integrated-circuit processing. Describes a monolithic circuit that decodes the 8-kHz companded PCM commonly used in voiceband communication systems. The circuit, realized in a standard buried collector bipolar technology, contains 300 integrated injection logic (I/SUP 2/L) gates together with a current-driven resistive ladder network. The performance of the decoder exceeds typical toll network objectives.