AS2540-T ams

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 Data Sheet AS2540 austriamicrosystems austriamicrosystems Remote Controlled Single-Chip-Telephone DATA SHEET (PRELIMINARY) AS2540 General Description Key Features The AS2540 is a CMOS integrated circuit that - Line Interface, Speech Circuit, MF Dialler and Tone Ringer incorporates a speech circuit (line-adaptation, 2/4-wire on a 28 pin CMOS chip conversion, separate Rx- and Tx-amplifiers for handset - Programmable via 2-wire serial interface and modem), MF dialler, ring frequency detector, ring (UART 9600 baud, 8N1) melody generator and a two wire serial interface. It - Watch dog timer for Backup Mode shall act as an a/b-line-powered device in order to - Additional input for modem transmit path interface a main-powered CPU to the analogue - Additional output for modem receive path telephone line. - CMOS for high EMC immunity - Low Noise (max. 72 dBm) AS2540 can operate in a so-called mainpower mode - Operating range from 15mA to 100mA (down to 5mA with and in a backup mode. During mainpower mode, a reduced performance) watchdog timer is running on AS2540, which has to be - Soft clipping for handset operation to avoid harsh distortion reset via the serial interface, which is connected to the - Line loss compensation selectable by pin option CPU through opto-couplers. During backup mode (= - Real and complex impedance selectable by external The main-power failure or SW engine problem), components - Side tone adaption selectable by external components AS2540 can operate as an independent basic MF dialler (digits 0-9* ) - Ring frequency discrimination - 3-tone ring melody generator Applications Package - Web Telephones - Answering Machines - 28 pin SOIC - Fax Machines - Dice-on-Foil - Base Station of Cordless Telephones - Hospital Communication Units Block Diagram Main Power Mode Backup Mode Line Line LS LS LI LI +6dB +6dB ROH ROH -2dB -2dB RI RI +2dB STB +2dB STB ROT ROT M1 M1 CS CS M2 M2 Mask Mask TIT TIT CI CI DPn DPn AGND AGND DTMF- DTMF- generator generator RxD RxD DIALLER UART TxD DIALLER UART TxD C1 C1 C2 C2 C3 C3 R1 R1 R2 R2 MODE MODE VDD VDD RFD RFD VSS VSS MO MO OSC EHS OSC EHS MHS MHS Revision 3.1 Page 1 of 18 ams AG Technical content still valid SDPn SMASK Dial Digit SMUTE STIT SROH SROT SDPn SMASK Dial Digit SMUTE STIT SROH SROT