U4091BM

The programmable telephone audio processor U4091BMis a linear integrated circuit for use in feature phones,answering machines and fax machines. U4091BM contains thespeech circuit, tone-ringer interface with DC/DCconverter, sidetone equivalent and ear-protectionrectifiers.  The circuit is line-powered and contains allcomponents necessary for signal amplification andadaptation to the line. The U4091BM can also be suppliedvia an external power supply. An integrated voice switchwith loudspeaker amplifier enables hands-free orloudhearing operation. With an anti-feedback function,acoustical feedback during loudhearing can be reducedsignificantly. The generated supply voltage is suitable fora wide range of peripheral circuits.