Hi, SilvioHi again Benny, the high frequency startup is because the IR2153 does not have a soft start. Charging the secondary capacitors at startup present a nearly dead short especially if having more than 2000uf on each of the center tap windings. However starting the trafo with 3 times the frequency cannot deliver that much current as this is wound for a lower frequency. This will reduce the stress on the mosfets and prevent them from burning.
Another way to eliminate this problem can be arranged by putting a 5R resistor on the VS line to limit the current and then this resistor can be bypassed by means of a relay after a couple of seconds after startup. Another idea comes in mind is adding an NTC thermistor on the VS line. However with an NTC you cannot start the smps while the thermistor is still warm as it will have no effect as its resistace would be very low.
I'm Benny from the IRS2153 I tested last year
I have now switched back to the IR2153 beta sub
lt is working normally without big problems.
But now this power supply finishes working after the power is turned off
The transformer will produce a noticeable hum that disappears after a few seconds
I think the capacitor or transformer is discharging too slowly?
Have you ever had a similar problem or have any suggestions?