DESCRIPTION

The UTC MC34118 voice switched speaker-phone integrated circuit incorporates the necessary amplifiers, attenuators, level detectors and control algorithm to form the heart of a high quality hands-free speaker-phone system. It includes a microphone amplifier with adjustable gain and mute control. Transmit and Receive attenuators which operate in a complementary manner, level detectors at both input and output of both attenuators, and background noise monitors for both the transmit and receive channels.

FEATURES

*Improved attenuator gain range: 52dB between Transmit and Receive

*Low voltage operation for line-powered applications(3~6.5V)

*4-point signal sensing for improved sensitivity

*Background noise monitors for both Transmit and Receive paths

*Microphone amplifier gain set by external Resistors-Mute function included

*Chip disable for active/standby operation

*On board filter pinned-out for user defined function

*Dial tone detector to inhibit receive idle mode during dial tone presence