A subscriber digital signal processor LSI for PCM applications

A single-chip subscriber digital signal processor LSI (SDP) having programmable codec functions, which utilizes oversampling conversions and digital signal-processing techniques, is described. The chip is fabricated using a standard 2- mu m CMOS technology, and integrates many additional functions for PCM (pulse-code modulation) applications, such as gain control, an autobalancing network, a three-party conference, and a metering signal circuit, which are controlled by a software program. Excellent system characteristics and low power dissipation are achieved with operation from a single +5-V power supply.<
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