Haier HT-2180 Service Manual page 29

Pin Function
40 Line AFC filtering
41 External video/Y signal input
42 Digital circuit grounding
43 PIF composite video signal input
44 Black level detection filtering
45 External chrominance signal input
46 Y/C circuit power supply
47 PIF and SIF composite signal
output
48 Intermediate frequency locked
phase loop filtering
49 VCO and SIF grounding
50 Intermediate frequency VCO
51 Intermediate frequency VCO
52 VCO and SIF power supply
53 SIF signal input and horizontal
curve correction
54 SIF smooth filtering
55 External audio input
56 FM DC negative feedback
Pin Function
1 Power supply grounding
2 Tuning voltage output
3 Vacant pin
4 Mute
5 External mute
6 Vacant pin
7 Standby power supply
8 Vacant pin
9 Band 1
10 Band 2
11 Clock bus control
12 Digit bus control
13 AFC input
14 Karaoke switch
15 Keyboard matrix input
16 Keyboard matrix input
17 Vacant pin
18 Vacant pin
Reference Voltage(V)
Without
signal
6.6
1.6
0
3.3
2.3
2.9
5.0
3.8
4.7
0
8.1
8.1
9.0
4.5
5.6
4.2
3.5
N901
Reference Voltage(V)
Without
signal
0
*
5.0
5.0
5.0
0
2.0
1~4.2
0~4.8
0~1.7
5.0
5.0
2.3
0
4.0
4.0
0
0
Reference Resistance(KΩ )
With signal
Forward(Ω)
6.6 800
1.6 800
0 0
3.3 800
2.3 800
2.9 800
5.0 500
3.8 680
4.7 800
0 0
8.1 550
8.1 650
9.0 450
4.5 820
5.6 800
4.2 800
3.5 800
TMP87CK38N(87CM38N)
Reference Resistance
With
Forward(Ω)
signal
0 0
* 700
5.0 700
0 700
0 700
0 700
2.0 700
1~4.2 700
0~4.8 700
0~1.7 700
5.0 700
5.0 600
2.3 700
0 600
4.0 700
4.0 680
0 700
0 700
28
Circuit Explanation
Backward(Ω)
2000
2000
0
2000
4000
2000
1200
900
2000
0
1000
1000
600
2000
1300
2000
2000
Backward(Ω)
0
8000
8000
8000
8000
8000
8000
8000
3500
3000
15000
15000
3000
10000
10000
10000
10000
10000