32
Model No: CT-14XJ9N
Version 1.0
3.
Repair data for IC TDA7057AQ(N601)
TDA7057AQ is the audio power amplifier OF CN-9, the pin functions and repair data
of it is listed in the table 5.
Table 5 Pin functions and repair data of TDA7057AQ
Index type multimeter (r=20k )
Resistance for GND
(RxlK)
Pin
Symbol
Function
Quiescent
state (v)
Dynamic
state (v)
Red pen
measure
Black pen
measure
1
VC1
Control pin for direct
current volume
0.96
0.96
13.5
6.2
2
N.C.
No connected
0
0
3
VI(1)
Audio signal input 1
2.38
2.38
18.7
6.4
4
Vp
Supply input pin
15
15
12.8
3.9
5
VI(2)
Audio signal input 2
2.38
2.38
6.4
6
S-GND
Signal ground
0
0
0
0
7
VC2
Control pin for direct
current volume
0.98
0.98
16.8
6.2
8
OUT2+
Audio signal output 2+
7.0
7.0
12.8
5.4
9
PGND2
Ground 2(supply circuit)
0
0
0
0
10
OUT2-
Audio signal output 2-
7.0
7.0
12.8
5.4
11
OUT1-
Audio signal output 1-
7.0
7.0
12.8
5.4
12
PGND1
Ground l(supply circuit)
0
0
0
0
13
OUTI+
Audio signal output 1+
7.0
7.0
12.8
5.4
4.
Repair data for IC LA7910(N101)
LA7910 is the band decoder of CN-9, the pin functions and repair data of it is listed
in the table 6.
Table 6 Pin functions and repair data of LA7910
Index type multimeter (r=20k )
Resistance for GND
(RxlK)
Pin
Symbol
Function
Quiescent
state (v)
Dynamic
state (v)
Red pen
measure
Black pen
measure
1
OUT1
Decoder output
0
0
2.1
2.1
2
OUT2
Decoder output 2
0
0
2.1
2.1
3
BD1
Band control level input 1
5
0
39
11
4
BD2
Band control level input 2
0
0
22
10
5
GND
Connect to ground
0
0
0
0
6
VC2
+33V supply input pin
33
13.5
5.8
25.5
7
OUT3
Decoder output 3
0
12
1.6
1.5
8
OUT4
Decoder output 4
0
0
0
12
9
VC1
+12V supply input pin
12
12
4.1
4.5
