TEA1085 Philips Semiconductors, TEA1085 Datasheet - Page 2

• Manufacturer Part Number: TEA1085
• Description: Listening-in circuit for line-powered telephone sets
• Manufacturer: Philips Semiconductors

Philips Semiconductors
FEATURES
ORDERING INFORMATION
Notes
1. SOT101-1; 1998 Jun 18.
2. SOT137-1; 1998 Jun 18.
March 1992
TEA1085/TEA1085A
TEA1085T/TEA1085AT
Internal supply
Loudspeaker amplifier
Larsen level limiter
Power down input
MUTE input
Listening-in circuit for line-powered
telephone sets
optimum current split-up
- low constant current (adjustable) in transmission IC
- nearly all line current available for listening-in
adjustable supply voltage
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
low sensitivity for own speech due to 3rd-order filter
and attack delay
adjustable voltage thresholds
TEA1085/TEA1085A
- clickfree switching between listening-in mode and
standby mode
TEA1085
- toggle function
- start-up in standby condition
TEA1085A
- logic level input
EXTENDED TYPE
NUMBER
PINS
24
24
PIN POSITION
SO24
DIL
2
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.
The circuits incorporate a supply circuit, loudspeaker
amplifier dynamic limiter, MUTE circuit, power-down
facility and logic inputs for gain setting. The devices also
incorporate a Larsen Level Limiter to reduce howling
effects.
The ICs are intended for use in conjunction with a
transmission circuit of the TEA1060 family.
PACKAGE
MATERIAL
plastic
plastic
TEA1085; TEA1085A
Preliminary specification
SOT101B
SOT137A
CODE
(1)
(2)