TEA1111A

INTEGRATED CIRCUITS DATA SHEET TEA1111A Speech circuit with dialler interface, regulated supply and earpiece volume control Product specification Supersedes data of 1999 Sep 28 File under Integrated Circuits, IC03 1999 Nov 22 Philips Semiconductors Product specification Speech circuit with dialler interface, regulated supply and earpiece volume control FEATURES Low DC line voltage; operates down to 1.5 V (excluding voltage drop across external polarity guard) Line voltage regulator with adjustable DC voltage 3.25 V regulated strong supply point for peripheral circuits compatible with: – Speech mode – Ringer mode – Trickle mode. Transmit stage with: – Microphone amplifier with symmetrical high impedance inputs – DTMF amplifier with confidence tone on earpiece. Receive stage with: – Earpiece amplifier with adjustable gain and volume control. MUTE input for pulse or DTMF dialling AGC line loss compensation for microphone and earpiece LED control output. APPLICATIONS TEA1111A Line powered telephone sets with LCD module Cordless telephones Fax machines Answering machines. GENERAL DESCRIPTION The TEA1111A is a bipolar integrated circuit that performs all speech and line interface functions required in fully electronic telephone sets. It performs electronic switching between speech and dialling. The IC operates at a line voltage down to 1.5 V DC (with reduced performance) to facilitate the use of telephone sets connected in parallel. When the line curren...