Lanix LX700R, Руководство по обслуживанию

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17" CDT Color Monitor Lanix LX700R
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5-2. Deflection Circuit
The deflection circuit is achieved by a high performance and efficient solution IC 401 (STV 9119) for this
monitor. The concept is fully DC controllable and can be used in applications with a micro-controller solutions.
The STV9119 provides sync. Processing with full auto sync. Capability, a flexible SMPS block and an extensive
set of geometry control facilities. Further the IC generates the drive waveforms for DC coupled vertical boosters
to the STV9302A.
Horizontal Oscillator
The oscillator is of the relaxation type and requires a capacitor of 100nF C403 at pin4.
PLL 1 Phase Detector
The phase detector is a standard one using switched current sources. It compares the middle of H-sync. With a
fixed point on the oscillator saw-tooth voltage. The PLL loop filter C422, C413, R405 is connected to Pin9.
PLL 2 Phase Detector
The PLL2 detector thus compensates for the delay in the external H-deflection circuit by adjusting the phase of
the HDRV output pulses. The phase between H-flyback and H-sync can be controlled at pin5.
X-ray Protection
The X-ray protection input pin25 provides a voltage detector with a precise threshold. If the voltage exceeds
this threshold for a certain time, an internal latch switches the whole IC into protection mode. In this mode
several pins are forced into defined states:
Pin6 (Co) is floating
Pin8 (Ro) is floating
Pin12, 13 (VOUT 12, 13) are floating
Vertical Oscillator
The vertical free
– running frequency is determined by the resistor C428 at pin21. Usually the free-running
frequency should be lower than the minimum trigger frequency.