U4089B-M

·Adjustable DC Characteristics
·Adjustable Transmit and Receive Gain
·Symmetrical Input of Microphone Amplifier
·Anti-clipping in Transmit Direction
·Automatic Line-loss Compensation
·Built-in Ear Protection
·DTMF and MUTE Input
·Adjustable Side Tone Suppression Independent of Sending and Receiving  Amplification
·Integrated Amplifier for Loud-hearing Operation
·Anti-clipping for Loudspeaker Amplifier
·Improved Acoustical Feedback Suppression
·Selectable Line Impedance
·Voice Switch
·Supply Voltages for All Functional Blocks of a Subscriber Set
·Operation Possible from 10-mA Line Current

·Feature Phones
·Answering Machines
·Fax Machines
·Speaker Phones

The telephone circuit U4089B-M is a linear integrated circuit for use in feature phones, answering machines and fax machines. U4089B-M contains the speech circuit, side tone equivalent and ear protection rectifiers. The circuit is line-powered and contains all components necessary for the amplification of signals and adaptation to the line. An integrated voice switch with a loudspeaker amplifier U4089B-M enables loud-hearing or hands-free operation. With an anti-feedback function, acoustical feedback during loud- hearing can be reduced significantly. The generated supply voltage is suitable for a wide range of peripheral circuits.