SPEECH NETWORK WITH DIALER INTERFACE
S1T8504
1
INTRODUCTION
The S1T8504 is a speech network which includes a Transmit Amp,
Receive Amp and DTMF Amp.
The gainis controlled automatically by sensing the line current.
The circuit internally performs electronic switching between dialing
and speech by the mute control.
FEATURES
Low line current operation
Mute function
DTMF signal interface
Easy gain control
ORDERING INFORMATION
BLOCK DIAGRAM
Device
Package
Operating Temperature
S1T8504X01-D0B0
16
-
DIP
-
300A
-
40
C to + 85
C
16
-
DIP
-
300A
13
12
1
RX INPUT
AMP
14
RX GAIN
CONTROL
RX OUTPUT
AMP
15
GAIN
CONTROLLER
TX AMP
2
3
TX GAIN
CONTROL
6
9
TX AMP
10
11
5
RXI
GC
V
L
CI
CO
MUTE
TOF
MIC-
MIC+
MF
RXO
ROF
S1T8504
SPEECH NETWORK WITH DIALER INTERFACE
2
PIN CONFIGURATION
PIN DESCRIPTION
Pin No
Symbol
Description
1
V
L
Positive power line and TX Amp Output.
2
CI
Current input.
3
CO
Current output.
If the line current is large, this pin dissipates excess power (current)
4
BIAS
AC signal reference voltage terminal.
5
MF
DTMF input.
If the mute pin set to High level, this pin goes to active state.
6
MUTE
Mute input.
If this pin set to High
level, speech signal muted and the DTMF input is enabled.
7
V
R
The voltage of this part becomes the reference voltage of internal Amp.
8
GND
Negative power line.
9
TOF
Output of the Mic Amp. Negative feedback to MIC -.
10
MIC +
Non inverting Mic input.
11
MIC
-
Inverting Mic input.
12
GC
Gain triggering point regulation.
13
RXI
Receiver input.
14
ROF
Receive Amp output and negative feedback to RX input.
15
RXO
Receiver Amp out.
16
V
CC
Internal power supply pin. Power is supplied from V
L
through resistor.
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
L
CI
CO
BIAS
MF
MUTE
V
R
GND
Vcc
RXO
ROF
RXI
GC
MIC-
MIC+
TOF
S1T8504
SPEECH NETWORK WITH DIALER INTERFACE
S1T8504
3
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(Ta = 25
C, f = 1kHz, unless otherwise specified)
Characteristic
Symbol
Value
Unit
Line Voltage
V
L
15
V
Line Current
I
L
150
mA
Surge Line Current (2 sec)
I
L (SURGE)
200
mA
Power Dissipation
P
D
1.0
W
Operating Temperature
T
OPR
-
40 to 85
C
Storage Temperature
T
STG
-
55 to 150
C
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
I
L
= 20mA
3.1
3.5
3.9
Line Voltage
V
L
I
L
= 50mA
5.4
6.0
6.4
V
I
L
= 120mA
10.5
11.5
12.5
I
L
= 20mA
1.7
2.0
2.3
Internal Operating Voltage
V
CC
I
L
= 50mA
3.3
3.7
4.1
V
I
L
= 120mA
7.2
7.6
8.0
TX Gain
G
V(TX)
I
L
= 20mA
35.0
37.0
39.0
dB
I
L
= 120mA
32.0
34.0
36.0
TX Dynamic Output Voltage
V
O(TX)
I
L
= 20mA, THD = 4.0%
2.5
-
-
Vp-p
I
L
= 120mA, THD = 4.0%
4.0
-
-
RX Gain
G
V(RX)
I
L
= 20mA
-
7.5
-
4.5
-
1.5
dB
I
L
= 120mA
-
13.5
-
1.5
-
7.5
RX Dynamic Output Voltage
V
O(RX)
I
L
= 20mA, THD = 10%
250
-
-
mVp-p
I
L
= 120mA, THD = 10%
300
-
-
RX Output Current
I
O (RX)
I
L
= 20 to 120mA
4.0
-
-
mA
DTMF Gain
G
V(MF)
I
L
= 20mA
20.5
22.5
24.5
dB
I
L
= 120mA
17.5
19.5
21.5
DTMF Input Impedance
Z
I (MF)
I
L
= 50mA
24
-
-
k
Mute Pin High Voltage
V
IH (MUTE)
I
L
= 20 to 120mA
1.5
-
V
CC
V
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