Description: The 821024 is a single-chip, four channel PCM CODEC with on-chip filters. The device provides analog-to-digital and digital-to-analog conversions and supports both a-law and m-law companding. The digital filters in 821024 provides the necessary transmit and receive filtering for voice telephone circuit to interface with time-division multiplexed systems. All of the digital filters are performed in digital signal processors operating from an internal clock, which is derived from MCLK. The fixed filters set t