U4030B - TEMIC Semiconductors

U4030B Telephone Speech Circuit

The U4030B is an electronic speech circuit for standard and feature telephones. It replaces the hybrid transformer, earphone and microphone interface and the supply voltage generation for external components, e.g. dialer or microcomputers. Using the U4030B in telephone circuit designs can improve transmission quality and results in cost savings through short.

Features

D Microphone amplifier with
  – Symmetrical input
  – Privacy function
  – Anticlipping D Built in ear protection D Power down input D Mute input D DTMF interface D Low line impedance during pulse dialing Benefits D Independent adjustment of
  – Transmission gain
  – Receiving gain
  – Sidetone suppression
  – Frequency response D Low-impedance supply voltage for all external blocks D Supply voltage for an electret microphone Applications D Standard telephone D Fax machine D Answering machine D Cordless telephone Block Diagram GT 11 DTMF PRIV MIC1 MIC2 10
  – + MICO 9 ST 5 +
  – GR 6
  – + Ear protection RECO .