GENERAL DESCRIPTION
The TEA1085 and TEA1085A are bipolar ICs which have been designed for use in line-powered telephone sets and provide a listening-in facility for the received line signal via a loudspeaker. Nearly all the line current can be used for powering the loudspeaker.

FEATURES
• Internal supply optimum current split-up
    - low constant current (adjustable) in transmission IC
    - nearly all line current available for listening-in adjustable supply voltage
• Loudspeaker amplifier dynamic limiter providing low distortion and the highest possible output power SE or BTL drive for loudspeaker volume control by potentiometer and/or logic inputs (e.g. microcontroller drive) fixed gain of 35 dB
• Larsen level limiter low sensitivity for own speech due to 3rd-order filter and attack delay adjustable voltage thresholds
• Power down input
• MUTE input
    TEA1085/TEA1085A
        - clickfree switching between listening-in mode and standby mode
    TEA1085
        - toggle function
        - start-up in standby condition
    TEA1085A
        - logic level input