Panasonic BT-M1950Y Service Manual page 111

5. Vertical circuit
The vertical sync signal processed by the signal PB ASS'Y is sent via CN001 pin 3 and buffer 0402 to IC001 pin 22.
IC00l produces a sawtooth waveform which goes via the IC101 buffer and CN003 pin 6 to IC403 pin 5. The V. out
waveform of the deflection yoke is also returned to pin 5. The DC offset voltage is applied to pin 6. When the pin 6 DC
voltage changes, the output DC level and IC401 input DC level also change. Since this DC level change varies the
vertical position, it is adjusted by the V center control.
+5V
TO
DIODE MOOVLATOR
PARABORA
our v.
BLK.
SYSTEM
AFC
V. TIMING PULSE
i.l 1•1v1
I .:J..JU I
FOR ON-SCREEN DISPLAY
V
V.
OUT
+12V
9V REGULATOR
Fig. 5-1 Vertical circuit
6. Vertical deflection processor IC
IC001 processes the waveforms required by the vertical deflection circuit. The IC can be controlled by the I2C bus.
The main pin functions are as follows;
Pin Function
Sawtooth output
11 Parabola output
20 V blanking pulse output
21 System detector output (High: NTSC, Low: PAL)
22 Vertical sync input
24 AFC correction signal output
26 12C bus serial clock input
30 12C bus data inpuVoutput
31 Power supply (
+
5 V)
35 Power supply (
+ 5 V)
36 Vertical sync timing pulse output
42 Zooming correction input
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