DESCRIPTION

The IDT821024 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 μ-law companding. The digital filters in IDT821024 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 the transmit and receive gain and frequency response.

FEATURES
• 4 channelCODECwith on-chip digital filters
• Selectable A-law orm-law companding
• Master clock frequency selection: 2.048 MHz, 4.096 MHz or
8.192 MHz
- Internal timing automatically adjusted based on MCLK and
frame sync signal
• Separate PCM and master clocks
• Single PCM port with up to 8.192 MHz data rate (128 time slots)
• Transhybrid balance impedance hardware adjustable via external
components
• Transmit gains hardware adjustable via external components
• Low power +5.0 V CMOS technology
• +5.0 V single power supply
• Package available: 32 pin PLCC, 44 pin TQFP