Reference Voltage(V)
Reference Resistance
Pin Function
Without
With
Forward(
Ω
) Backward(
Ω
)
signal
signal
34 Vacant
pin
4.8
700
10000
35
Infrared receiving input
3.8
700
10000
36 Line synchronizing signal
input
4.2 700 10000
37
Clock bus control
0.8
700
10000
38
Data bus control
3.0
700
10000
39 Vacant
pin
4.2
700
10000
40 Vacant
pin
4.2
700
10000
41 Vacant
pin
0
700
10000
42 Power
supply
5.0
420
2700
N101 LA7910
Reference
Voltage(V)
Reference Resistance
Pin Function
Without signal
Forward(K
Ω
) Backward(K
Ω
)
1 Output
(BU)
0
120
7.2
2 Output
(BH)
12.5
17.5
7.5
3 Control
input
12.5
6.5
8.5
4 Control
input
0
6.5
9.0
5 Grounding
terminal
0
0
0
6
Power input terminal 1
14.0
6.0
50
7 Output
(BL)
0
1.5
1.5
8 Vacant
pin
0
8.5
9
Power input terminal 2
9
0.5
0.5
3. Signal processing
(1)
Picture intermediate signal processing
Having been under tuning and selective calling, high frequency amplification and frequency
mixing in tuner A101, the high frequency signals are output through the intermediate
frequency signal output terminal (IF) of A101 to the base electrode of intermediate frequency
pre-amplifier V101 via the coupling matching network. The intermediate signals are added to
Pin 6 and 7 of the symmetric terminals of the intermediate difference channel of the TV signal
monolithic processing circuit N201 (TB1238N). The intermediate signals are amplified in
N201 and the PLL picture modulated. The mixed signals of picture video and the second
sound are output from Pin 47 and then divided into two.
(2)
Picture signal processing