SL34118
Voice Switched Speakerphone Circuit
The SL34118 Voice Switched Speakerphone Circuit incorporates the necessary
amplifiers, attenuators, level detectors, and control algorithm to form the heart of a high quality hands-free speakerphone system.
Included are 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.
A Dial Tone Detector prevents the dial tone from being attenuated by the Receive background noise monitor circuit.
Also included are two line driver
amplifiers whi...