Samsung KCT52A, Training Manual

Page: 14 / 93

KCT52A Chassis
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TOC
14
Power Supply Description
Over Voltage Protection Circuit Description
The overvoltage protection circuit activates the latch circuit
when the Vin voltage exceeds about 11V.
Since Vin is proportional to the load voltage, the OVP circuit
will trigger the latch circuit when an abnormally high voltage
appears on the load line due to the open loop in the feedback
path.
Overheat Protection Circuit Description
When the control IC's temperature reaches over 150 degree C,
the latch circuit is activated.
Actual temperature detection is done through the control cir-
cuit mounted on the IC frame internally.
Latch Circuit Description
The latch circuit stops oscillation of the control IC when OVP
or Overheat condition occurs.
When this happens, the Vin voltage will fluctuate between the
Stop voltage and the Operation voltage continuously.