Switching Power Supply FAQ
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Frequently Asked Questions
No DC voltage output or voltage output unstable
Delivery time:2015-9-25 Num：1843
If the fuse is intact and under load conditions, there is no output
DC voltage levels. This is mainly due to the following reasons: The power of an
open circuit, short circuit, overvoltage, overcurrent protection circuit fails,
auxiliary power failure, the oscillation circuit does not work, power overload,
the circuit rectifier diode breakdown, filter capacitor leakage and so on. After
measuring the secondary components with a multimeter, excluding high-frequency
rectifier diode breakdown, load short-circuit, the output is zero if the time,
you can be sure that the power control circuit a fault. If part of the voltage
output, the front-end circuit is working properly, the fault lies in the
high-frequency rectifier filter circuit. High-frequency filter circuit mainly by the
rectifier diode and low pressure filter capacitors, rectifier diode breakdown
would no voltage output of the circuit; the output filter capacitor leakage
will cause voltage instability and other failures. Corresponding elements can
be measured with a multimeter to check out its damaged components.