Degauss Ckt; Overload Protection Ckt - Acer AC 711 Service Manual

F. DEGAUSS CKT:
The DEGUSS signal which comes from micro-p to control degauss coil act or not.
When DEGUSS is high, Q950 will be saturated to make RL901 working, AC line provides a
degaussing current to degauss coil.
G. OVERLOAD PROTECTION CKT:
The primary current flows through the current sensing resistor R907.
The sensing voltage through the R907, R911, C914 to U901 pin3, If the current up, the
U901 pin 3 voltage will be follow up, When the voltage>1 V, the U901 duty-cycle shall be
limited, Made the output voltage down in the meanwhile make the U901 VCC voltage down,
the U901 pin 7 fall down under 10 voltage in the then, U901 stop action, made over load for
protection.
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