GENERAL DESCRIPTION

ST5088 PIAFE is a combined PCM CODEC/FILTER device optimized for ISDN Terminals and Digital Telephone applications. This device is A-law and Mu-law selectable and offers a number of programmable functions accessed through a serial control channel.

FEATURES:

■ Complete CODEC and FILTER systemincluding:

■ PCM ANALOG TO DIGITAL AND DIGITAL TO ANALOG CONVERTERS

■ POWERFUL ANALOG FRONT END CAPABLE TO INTERFACE DIRECTLY:

- Microphone Dynamic or Electrete

- Earpiece down to 100Ω or up to 150nF

- Loudspeakerdown to 50Ω or Buzzer up to 600nF.

■ TRANSMIT BAND-PASS FILTER

■ ACTIVE RC NOISE FILTER

■ RECEIVE LOW-PASS FILTER WITH SIN X/X CORRECTION

■ MU-LAW OR A-LAW SELECTABLE COMPANDING CODER AND DECODER

■ PRECISION VOLTAGE REFERENCE

Phones Features:

■ DUAL SWITCHABLE MICROPHONE AMPLIFIER INPUTS. GAIN PROGRAMMABLE: 15 dB RANGE, 1 dB STEP.

■ LOUDSPEAKER AMPLIFIER OUTPUT. SWITCHABLE MAXIMUM GAIN: +9dB/+27dB WITH AUTOMATIC DIGITAL ANTICLIPPING SYSTEM. aTTENUATION PROGRAMMABLE: 30dB RANGE, 2dB STEP.

■ SEPARATE EARPIECE AMPLIFIER OUTPUT. ATTENUATION PROGRAMMABLE: 15 dB RANGE, 1 dB STEP.

■ AUXILIARY TAPE RECORDER ANALOG INTERFACE: Tx + Rx COMBINED OUTPUT.

■ AUXILIARY SWITCHABLE EXTERNAL RING INPUT (EAIN).

■ TRANSIENT SUPRESSION SIGNAL DURING POWER ON.

■ INTERNAL PROGRAMMABLE SIDETONE CIRCUIT. ATTENUATION PROGRAMMABLE: 15 dB RANGE, 1 dB STEP, INDEPENDENT FROM Rx CONTROL.

■ INTERNAL RING OR TONE GENERATOR INCLUDING DTMF TONES, SINEWAVE OR SQUAREWAVE WAVEFORMS. ATTENUATION PROGRAMMABLE: 27 dB RANGE, 3 dB STEP.

■ RINGER CONTROL PROGRAMMABLE INTERNALLY (µP) OR EXTERNALLY (pin AT)

■ COMPATIBLE WITH HANDS-FREE CIRCUIT TEA7540.

■ ON CHIP SWITCHABLE ANTI-ACOUSTIC FEED-BACK CIRCUIT (ANTI-LARSEN).

General Features:

■ EXTENDED TEMPERATURE RANGE OPERATION (*) – 25°C TO +85°C.

■ EXTENDED POWERSUPPLYRANGE 5V±10.

■ 60 mW OPERATING POWER (TYPICAL).

■ 1.0 mW STANDBY POWER (TYPICAL).

■ CMOS DIGITAL INTERFACES.

■ SINGLE + 5V SUPPLY.

■ DIGITAL LOOPBACK TEST MODE.

■ PROGRAMMABLE DIGITAL AND CONTROL INTERFACES:

–Digital PCM Interface associated with separate serial Control Interface MICROWIRE™ compatible.

–GCI interface compatible.

APPLICATIONS:

■ ISDN TERMINALS.

■ DIGITAL TELEPHONES

■ CT2 AND GSM APPLICATIONS