
LA7858
No.3314-5/8
Sample Application Circuit : 14” display
Vertical retrace time
≈ 300μs
Vert.
Trig.
Input
One
Shot
Multi
Vert.
Size
Control
S.W
Ramp Generator
Vert. Drive
Thermal Protection
vert. Out
Pump Up
LA7837, LA7838
LA7858
+
+VCC8
+
C1
24V
R6
1.5
Ω
D.Y
10pF
Vert. Sync. Pulse
Vert. Hold
Hor. Sync. Pulse
100pF
Vert. OSC.
Vert. Ramp Generator
Phase
Shifter
Saw Tooth
Generator
AFC
Hor. OSC.
Xray
Protector
Hor. Hold
Hor
Pulse
Duty
Hor. Driver
H. D
6800pF
at
15.734kHz
at
15.732kHz
5600pF
+VCC H
(12V)
Flyback Pulse
+VCC V
(12V)
+VCC V
270pF
(470pF)
1
2
3
4
5
6
7
8
9
10
11
12
13
22
21
20
19
18
17
2
4
5
6
7
8
9
10 11 12
13
14
22k
Ω
R3
12k
Ω
R5
39k
Ω
100
μF
1
μF
Tantalum
100
μF
R2
47k
Ω
R4
1k
Ω
C3
1000
μF
1
μF
50k
Ω
Vert. Height. Vol
0.001
μF 47kΩ
200k
Ω
220
μF
10
μF
180k
Ω
22k
Ω
0.1
μF
2.2k
Ω
22k
Ω
(12k
Ω)
12k
Ω
(22k
Ω)
VR1
20k
Ω
VR2
50k
Ω(
30k
Ω)
22k
Ω
8.2k
Ω
1
μF
1
μF
0.01
μ
F
33k
Ω
1k
Ω
12k
Ω
5k
Ω
22
μF
15k
Ω
VR4
20k
Ω
3.3k
Ω
4.7
μF
C2
Zener
2SC536
×2
15k
Ω
16
15
1000pF
( ) : For negative
polarity pulse.
Change VR2 to fixed constant after adjustment.
Fig.2