TEA7091 Datasheet, PDF (1/7 Pages) STMicroelectronics – TELEPHONE ANALOG FRONT END

TEA7091
TELEPHONE ANALOG FRONT END
PRODUCT PREVIEW
FEATURES:
SPEECH
DC LINE CURRENT RANGE FROM 6 TO
110mA
Tx AND Rx GAIN EXTERNALLY ADJUST-
ABLE
AGC IN Tx AND Rx EXTERNALLY PRO-
GRAMMABLE
AGC DISABLEABLE THROUGH MICROCON-
TROLLER BUS
SINGLE/DOUBLE SIDETONE NETWORK
SOFTWARE PROGRAMMABLE
SOFTCLIPPING ON Tx CHANNEL
SQUELCH TO REDUCE Tx NOISE ENVI-
ROMENT AND TO IMPROVE HOWLING IM-
MUNITY IN LOUDHEARING MODE
RECEIVING AMPLIFIER FOR PIEZO OR
ELECTRODYNAMIC TRANSDUCERS
+6dB MODE ON Rx CHANNEL (SELECTABLE
THROUGH MICROCONTROLLER BUS)
–6dB MODE ON Tx CHANNEL (SELECTABLE
THROUGH MICROCONTROLLER BUS)
FREQUENCY GENERATOR FOR WAITING
MELODY
ERROR BEEP GENERATOR
HOLD LINE CURRENT DETECTOR FOR
TRANSFER/ AUTO RELEASE
GROUP LISTENING / ON-HOOK DIALING
ANTI HOWLING WITH ACOUSTIC FEED-
BACK SYSTEM COUPLED WITH SQUELCH
DIGITAL VOLUME CONTROL (8 STEPS OF
4dB EACH) THROUGH MICROCONTROL-
LER BUS
ANTILARSEN ATTENUATION (4 DIFFERENT
LEVELS) PROGRAMMABLE THROUGH MI-
CROCONTROLLER BUS
HANDSFREE INTERFACE
PIN AND SOFTWARE FACILITY FOR EASY
INTERCONNECTION WITH HANDSFREE
CONTROLLER IC.
PLCC44
PQFP44
PLY TO FEED THE LOUDSPEAKER AMPLI-
FIER DURING RING MODE
DIGITAL VOLUME CONTROL (8 STEPS OF
4dB EACH) THROUGH MICROCONTROL-
LER BUS
RING FREQUENCY GENERATOR PRO-
GRAMMED THROUGH MICROCONTROL-
LER BUS
DIALLING
DTMF GENERATOR (CONTROLLED BY
MCU BUS)
DC MASK VALUE DURING MAKE PERIOD
PROGRAMMABLE THROUGH MICROCON-
TROLLER BUS
MICROCONTROLLER INTERFACE
STABILIZED VOLTAGE FOR MICROCON-
TROLLER
2 WIRE SERIAL BUS
RING INDICATOR
POWER-ON SIGNAL
RESET SIGNAL
LINE CURRENT VARIATION INDICATOR
RING ON LOUDSPEAKER
EMBEDDED SWITCH MODE POWER SUP-
SELF BIASED LOUDSPEAKER AMPLIFIER FOR
ANSWERING MACHINE
September 1993
1/7
This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.