Power Supply Board - Epson LQ-1170 Service Manual

The +35 VDC line has a voltage overload protection circuit and a voltage drop protection circuit. The
+35 V voltage overload protection circuit cuts the supply if the voltage reaches or exceeds +36 VDC.
It stops switching circuit operation, which stops the output of the +35 VDC line. The voltage drop
protection circuit protects the printer from damage that might occur if the secondary circuitry
+35 VDC line short circuits. If a voltage drop is detected, it stops switching circuit operation,
stops the output of the +35 VDC line.
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Prim a ry
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AC Input

Power Supply Board

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Figure 2-16. Power Supply Circuit Block Diagram
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+5
line
Voltage
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Overload
Protection
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Circuit
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+35
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Overload
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+5
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Power
Switch
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