GENERAL DESCRIPTION

The AD28msp01 is a complete analog front end for high performance DSP-based modems. The device includes all data conversion, filtering, and clock generation circuitry needed to implement an echo-cancelling modem with a single host digital signal processor. Software-programmable sample rates and clocking modes support all established modem standards. The AD28msp01 simplifies overall system design by requiring only +5 volts.

FEATURES

Complete Analog l/O Port for DSP-Based FAX/MODEM Applications

Linear-Coded 16-Bit Sigma-Delta ADC

Linear-Coded 16-Bit Sigma-Delta DAC

On-Chip Anti-Alias and Anti-lmage Filters

Digital Resampling/lnterpolation Filter

7.2 kHz, 8.0 kHz, and 9.6 kHz Sampling Rates

8/7 Mode for 8.23 kHz, 9.14 kHz, and 10.97 kHz Sampling Rates

Synchronous and Asynchronous DAC/ADC Modes

Bit and Baud Clock Generation

Transmit Digital Phase-Locked Loop for Terminal Synchronization

Independent Transmit and Receive Phase Adjustment

Serial Interface to DSP Processors

+5 V Operation with Power-Down Mode

28-Pin Plastic DlP/44-Lead PLCC/28-Lead SOIC

APPLICATIONS

High Performance DSP-Based Modems

V.32ter, V.32bis, V.32, V.22bis, V.22, V.21,

Bell 212A, 103

Fax and Cellular-Compatible Modems

V.33, V.29, V.27ter, V.27bis, V.27, V.26bis

Integrated Fax, Modem, and Speech Processing