MT9123

CMOS Dual Voice Echo Canceller

Description

The Voice Echo Canceller implements a cost effective solution for telephony voice-band echo

cancellation conforming to ITU-T G.165 requirements. The MT9123 architecture contains two echo cancellers which can be configured to provide dual channel 64 millisecond echo cancellation or single channel 128 millisecond echo cancellation.

Features

• Dual channel 64ms or single channel 128ms echo cancellation

• Conforms to ITU-T G.165 requirements

• Narrow-band signal detection

• Programmable double-talk detection threshold

• Non-linear processor with adaptive suppression threshold and comfort noise insertion

• Offset nulling of all PCM channels

• Controllerless mode or Controller mode with serial interface

• ST-BUS or variable-rate SSI PCM interfaces

• Selectableµ/A-Law ITU-T G.711; µ/A-Law Sign Mag; linear 2’s complement

• Per channel selectable 12 dB attenuator

• Transparent data transfer and mute option

• 19.2 MHz master clock operation

Applications

• Wireless Telephony

• Trunk echo cancellers