General Description

The multichannel programmable codec chip set is comprised of the T8531A 16-channel line card signal processor and one or two custom T8532 octal A/D and D/A converters. A ROM-coded tone plant, with line-test and self-test utilities, is included on the signal processor. Together these devices achieve a highly integrated and highly programmable multichannel voice codec solution.

Software is provided to compute the gain and filter coefficients required to program the codec.

Features

■ Per-channel programmable gain and hybrid balance

■ Programmable termination impedances

■ Programmable μ-law, A-law, or linear PCM output

■ Tone plant:

— DTMF generator

— DTMF receiver

— Caller ID generator

— Call progress tones generator

■ Test utilities:

— Automatic gain calibration

— Tone generation

— dc generation

— dc measurement

— Variance computation

— Peak detection

■ Analog and digital loopbacks

■ Programmable time-slot assignment with bit offset

■ Low-noise, balanced, receive SLIC interface

■ Few or no SLIC/codec interface components required

■ Sigma-delta converters with dither noise reduction

■ Serial microcontroller control interface

■ Meets or exceeds ITU-T G.711—G.712 and relevant Telcordia Technologies? requirements

■ Available in 64-pin MQFP and TQFP packages