U4037B Datasheet, PDF (2/6 Pages) TEMIC Semiconductors – LOW VOLTAGE SPEECH CIRCUIT WITH TONE RINGER INTERFACE

U4037B
Block Diagram / Applications
Tip
Ring
620 W
DTMF
RDC
22 mF
VI
SWAMP
AGC
MUTE
MIC1 MIC2 MICO
Microphone ^–
amplifier +
Mute control
Supply current
regulator
AGC current
generator
TIN
Control
function
Transmit
amplifier _VL
Sidetone
amplifier
ST
Receiver
attenuation ^RECIN
Receiving
amplifier
RECO1
RECO2
VDD
VOL1
VOL2
MELI
Receive volume
control
Ringer volume
control
GND
Supply
Bandgap
reference
Comparator
with hysteresis
VB
OUT
9879
RFO
to mC
Figure 1. Block diagram
2 (6)
TELEFUNKEN Semiconductors
Preliminary Information
Rev. A1, 08-Oct-96