U4091B

·Speech circuit with anti-clipping
·Tone ringer interface with dc / dc converter
·Speaker amplifier with anti-distortion
·Power supply management, regulated, unregulated and a special supply for electret microphone
·Voice switch

Feature phone, answering machine, fax machine, speaker phone

The programmable telephone audio processor U4091B is a linear integrated circuit for use in feature phones, an- swering machines and fax machines. It contains the speech circuit, tone ringer interface with dc/dc converter sidetone equivalent and ear protection rectifiers. The cir- cuit is line powered and contains all components necessary for amplification of signals and adaptation to the line.
An integrated voice switch with loudspeaker amplifier U4091B allows handsfree or loudhearing operation. With an anti-feedback function, acoustical feedback during loud- hearing can be reduced significantly. The generated supply voltage of U4091B is suitable for a wide range of peripheral circuits.