AN618 Panasonic Semiconductor, AN618 Datasheet - Page 18

• Manufacturer Part Number: AN618
• Description: Recording and playing amplifier IC for answering telephones
• Manufacturer: Panasonic Semiconductor

AN6175K
18
Pin No.
Detailed Pin Descriptions(cont.)
18
19
20
21
22
23
TAO
RAO
APC
DI
DO
GND
Symbol
[Receiver att. output(hands-free mode)]
The receiver attenuator outputs receiver
signals in the HF mode from this pin
through C29(0.1
Pin27 as the loudspeaker preamplifier
non-inverse input. The output impedance,
Zout=1 k .
[Auto. PAD current control(handset
The ratio of R24 to R25 as connected to
this pin controls the operation point of the
automatic PAD.
[Receiver amp. input(–)]
Combined R26, R27, and C21 as con-
nected to this pin determine the gain of
the receiver amplifier.
[Receiver amp. output]
Connects through C22(22 F)to the hand-
set receiver. The output impedance,
Zout=100 .
[Ground]
This is the ground pin of the IC.
[Transmitter
mode)]
The transmitter attenuator outputs trans-
mitter signals in the HF mode from this
pin to Pin36 through C37(0.1 F). The
output impedance, Zout=1 k .
mode, MF)]
Description
att.
F)and R30(10 k )to
output(hands-free
APC
VGR
21
20
40
Equivalent circuit
BGR
1.2V
ICs for Telephone
22
18
19