TOVIS P/N
MTG-1972XN
DATE
2002.03.11
REV NO.
0
TOVIS
Color Monitor Service Manual
PAGE
22/30
8-2. Deflection Processor (IC301)
8-2.1. Horizontal section
1) Horizontal oscillation
R314 and C347 set horizontal free frequency to 48KHz.
Auto-sync processing can be done from 30KHz to 70KHz by mean of
IC301 without any adjustment.
2) Phase shift
Horizontal phase shift is controlled by IC601 using I
2
C BUS control.
3) Horizontal driver output
The output pulse, which has the duty-cycle of 47%, is available at pin
26 of IC301.
This output is used for horizontal drive circuit.
4) B+ control driver output
The output pulse is available at pin 6 of IC301 and it is used for
H-scan voltage control driver.
5) X-ray protection
When the fly-back voltage rises up to unacceptable level X-ray
protection is activated X-ray input pin 13 of IC601 is above 4V.
This result is that the completed line drive stage stops working.
The reset of this protection is obtained by Main power off.
8-2.2. Vertical section
1) Vertical oscillation
The free running frequency of the vertical oscillator is determined by
the capacitor C342 at pin VCAP (pin22) of IC301.
2) Vertical amplitude
Vertical amplitude is controlled by IC601 using I
2
C.
3) Vertical position
Vertical position is controlled by IC601 using I
2
C.
4) East-west parabola
A parabola waveform is available on pin 24 of IC301 for driving the
pincushion correction stage. Amplitude of parabola waveform is
controlled by IC601 using I
2
C.
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