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Order this document by MC33219A/D MC33219A Voice Switched Speakerphone VOICE SWITCHED The Motorola MC33219A Voice Switched Speakerphone Circuit SPEAKERPHONE CIRCUIT incorporates the necessary amplifiers, attenuators, level detectors, and control algorithm to form the heart of a high quality hands–free SEMICONDUCTOR speakerphone system. Included are a microphone amplifier with mute, TECHNICAL DATA transmit and receive attenuators, a background monitoring system for both the transmit and receive paths, and level detectors for each path. An AGC system reduces the receive gain on long lines where loop current and power are in short supply. A dial tone detector prevents fading of dial tone. A Chip Disable pin permits conserving power when the circuit is not in use. The volume c