STTH110 diode applied to two-tube forward excitation circuit with short circuit and broken and blown out

[Lihuigao]

Hello,

I am using ‘STTH110’ as a power supply for magnetic reset of two-tube forward circuit.

We are using ‘STTH110’ as a power supply for magnetic reset of two-tube positive excitation circuit, and there are diode breakage and short-circuit failures during batch aging, and we need your technical support to find out the cause of the problem.

We have checked the current and voltage stress on the diodes in the circuit application and none of them exceeded the requirements of the specification.

Below is the circuit diagram of our application and the waveform test graph of ‘STTH110’.

Is there any way to locate the cause of the problem? Or is there any other way to determine the cause?

*This post has been translated from Chinese to comply with the ST Community guidelines.