Daewoo DTH-14Q1FS, Руководство по обслуживанию

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when the latch cirguit is on. V
IN
terminal voltage increases and decreases with- in the range from 4.9V typical to
8V typical and is prevented from abnormally rising. Fig. 12 shows an example of V
IN
terminal voltage
waveform.Cancellation of the latch-is done by decreasing V
IN
terminal voltage below 3.3V. The power supply
can be restarted after disconnecting an AC input to the power supply once.
8) Thermal shutdown, circuit
It is a circuit to trigger the latch circuit when the frame temperature of the IC exceeds 150°C (typical). Although
the temperature is actually sensed at the control chip. It works against overheating of the power transistor as
the power transistor and the control IC are mounted on the same lead frame.
9) Overvoltage protection circuit
It is a circuit to trigger the latch circuit when V
IN
terminal voltage exceeds 11V (typical). Although it basically
functions as protection of V
IN
terminal against overvoltage, since V
IN
terminal is usually supplied from the drive
winding of the transformer and the voltage is proportional to the output voltage, it also functions against the
overvoltage of secondary output which causes when the control circuit opens or in some other events.
Fig 12 Typical V
IN
Terminal Voltage Waveform When Latch Circuit Is Operating
8V
(TYP)
VIN
4.9V
(TYP)
0