Philips Semiconductors
Low voltage versatile telephone transmission circuit
with dialler interface and transmit level dynamic limiting
Product specification
TEA1064A
andbook, full pagewidth
R16
56 Ω
Vi
C1 100 µF
Ip
10
µF
C15
220
µF
Vi
19 16
13 VCC2 VCC1
IR
R15
392 Ω
R1
620 Ω
1
LN
QR− 4
9
MIC+
8
MIC−
12
DTMF
TEA1064A
QR+ 5
R4
100
GAR 6 kΩ
14
MUTE
15
PD
7
DLS/MMUTE
VEE
REG
AGC
2
GAS1
R7
68
3 kΩ
GAS2
STAB SLPE
11
17
18
10
20
C16
470 nF
C3
R5
470
R6
3.6
R9
nF
kΩ
20 Ω
100 µF
RL
600 Ω
C4
100 pF
C7 1 nF
C6
100 pF
Iline
Vo
11 to
140 mA
MGR076
For measuring the gain from MIC+ and MIC− the MUTE input should be LOW
or open-circuit; for measuring the DTMF input, the MUTE input should be HIGH.
Inputs not being tested should be open-circuit.
Fig.22 Test circuit for defining voltage gain of MIC−, MIC+ and DTMF inputs; voltage gain (Gv) is defined as
20 log Vo / Vi .
March 1994
24