TEA7532 - ST Microelectronics

TEA7532 MONITOR AMPLIFIER

This 16 pins IC is designed for monitor (loudspeaker) telephone set and provides : a) Signal amplification for monitoring (loudspeaker) b) Antiacoustic feedback (antilarsen) c) Antidistortion by automatic gain adaptation d) Antilarsen adjustment (full duplex) BLOCK DIAGRAM DIP16 SO16 ORDERING NUMBERS : TEA7532DP (DIP16) TEA7532FP (SO16) July 1993 1/16 .

Features

of each exist in different frequency bands. To extract the larsen component, the microphone signal is first filtered by a second order filter (formed Figure 16. by two first order filters), then amplified and rectified in order to produce the AGC control signal. Zin : 4 kΩ A= V7 V5
  – V6 = 15 The first filter is generated by the capacitors on pins 5 and 6 ; the second filter by the R-C network on pin 7. 8/16 TEA7532 Figure 17 : Antilarsen System Filter Response. Filter on pins 5 & 6 f2 = C9 + C10 2π Zin C9 C10 Filter on pin 7 f1 = 1 2π (R5 + R6) C5 1 2π R5 C5 f3 = Antilarsen system F.