1.
The integrated circuit used in this set
(1) TB1238AN: Picture intermediate frequency, sound intermediate frequency, video
signal processing, chrominance signal processing, RGB output circuit and horizontal
and vertical vibration scanning circuit.
(2) TMP87CK38N: Super central microprocessor
(3) LA7830: Vertical scanning circuit.
(4) LA4275: Sound amplifier circuit.
(5) LA7910: Band alternating selection switch
2. Functions and parameters of integrated circuit
N402 LA7830
Reference resistance (K
Ω
)
Item
No.
Function Reference
voltage
(V)
Forward Reverse
1 Grounding
terminal
0
0
0
2 Output
terminal
13
0.45 1.9
3
Pump power output
terminal
26 0.5
∞
4 Vertical
scanning
saw-tooth wave signal
input terminal
0.95 0.9
0.25
5 Vertical
scanning
saw-tooth wave signal
generating terminal
0.75 0.68
1.75
6
Vertical power terminal
26
0.5
2.95
7
Vertical power input
terminal
0.83 0.65
1.3
N701 LA4275
Reference resistance (K
Ω
)
Item
No.
Function Reference
voltage
(V)
Forward Reverse
1 Ground
0
0
0
2 Amplifier
output
10
0.55 4.5
3 Power
supply
19
0.42 2.8
4 Ripple
filtering
10
1.2 2.4
5 Ground
0
0
0
6 Audio
input
0.1
1.1
∞
7 feedback
0.2 0.72
2.0