AS2525F AMSCO [austriamicrosystems AG], AS2525F Datasheet - Page 3

• Manufacturer Part Number: AS2525F
• Description: Single-Chip Handsfree Phone CMOS Integrated Circuit
• Manufacturer: AMSCO [austriamicrosystems AG]

Datasheet AS2525
Revision 2.1
Pin #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
Symbol
DM/HM
RECV
RECI
A
CBN
OSC
V
LO1
LO2
LED
CLK
V
V
FCI
RO
CM
R1
R2
R3
C1
C2
C3
C4
DI
GND
SSA
DD
PP
Supply
Supply
Supply
Supply
Type
DI/O
DI/O
AO
DO
AO
DO
DO
DI
DI
DI
AI
AI
AI
REC
Analogue input for the handsfree receive path. Should be connected to RO via a coupling
capacitor.
REC
Analogue input for receive voice switching path.
R
Output for driving a dynamic earpiece with an impedance from 150
V
Positive Power Supply.
A
Special ground for the internal amplifiers.
Analogue input pin for connecting a capacitor for background noise monitoring.
C
This is an output for controlling the external switching converter. During ringing it converts
the ring signal into a 4V supply voltage.
Loudspeaker Power Supply
High power supply for the output driver stage.
L
Output pins for a 32
Power supply pin for LO1-LO2 output amplifier.
D
Digital input for choosing between LD and MF dialing or choosing handset and headset
mode. See “Table 3: Parameter settings” for further details. This pin is scanned after manual
off-hook only.
F
This is a Schmitt-trigger input for ring frequency discrimination. Disabled during off-hook.
LED
Digital output for connecting 2 mA LED to indicate handsfree mode.
Osc
Input for ceramic resonator 3.58 MHz.
Keyboard
(see Figure 1: Keyboard Layout).
Keyboard
(see Figure 1: Keyboard Layout).
Cl
Clock output for 3-wire bus.
If signal is not activated, a pull down resistor (100 k ) is inserted.
D
Data input of 3-wire bus.
If signal is not activated, a pull down resistor (100 k ) is inserted.
oudspeaker
requency
oltage
nalogue
eceive
onverter
ial
ata
oc
M
illator Input
k
eive
eive
I
Output
nput
ode/
D
O
R
C
G
I
V
rain
M
utput to
nput
C
H
ows
olumns
oice Switching Input
rou
ake Output
omparator
O
eadset
D
nd
utputs
rain
H
M
andset
1/2
ode Switch Input
( 25 to 50
I
nput
) loudspeaker.
Description
austriamicrosystems
to 300
.
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