austriamicrosystems AG is now ams AG The technical content of this austriamicrosystems datasheet is still valid. Contact information: Headquarters: ams AG Tobelbaderstrasse 30 8141 Unterpremstaetten, Austria Tel: +43 (0) 3136 500 0 e-Mail: ams sales ams.com Please visit our website at www.ams.com austriamicrosystems Telephone Line Interface and Speakerphone Circuit DATA SHEET AS2522B Key Features General Description - Line/Speech circuit, DTMF dialer, FSK transmitter and AS2522 is a CMOS integrated circuit that incorporates DC tone ringer on a 32-pin CMOS-IC and AC line adaptation (DC-mask and synthesized AC- - Enhanced voice switching impedance of 1000 ) as well as a speech circuit with - Background noise monitoring softclipping, line loss compensation and Rx-volume control - DTMF tone generator for handset and handsfree operation. It shall act as an a/b- - FSK Transmitter V.23, BELL202, V.21, BELL 103 line powered device, which is controlled by a CPU via a - Ringer tone programmable serial interface. Furthermore the AS2522 incorporates a - Tx- and Rx-gain programmable DTMF, FSK transmitter, single tone and ringer tone - Digital volume control of Rx signals generator. - DC characteristic programmable - Dual softclipping in handset mode AS2522 allows to use an off-the-shelf microprocessor - Tx-softclipping in handsfree mode without special blocks and functions for telephone - Common monitor amplifier for loudhearing, handsfree applications. DTMF, FSK transmitter, single tone and ringer and ringing tone generator can be controlled via the serial interface as - Supply voltage generation for external circuitry well as the gain settings in handset and handsfree mode. - Automatic line loss compensation (LLC) - Real and complex impedance selectable by external Applications components Enhanced handsfree feature phones with CallerID and - Side tone adaptation selectable by external components extended displays. - Unique EMC performance - Operating range from 15mA to 100mA (down to 5mA with reduced performance) Package - Few external components Available in 32-pin TQFP Block Diagram Revision 3.4 Page 1 of 19 ams AG Technical content still valid