Part Number:UCC28910
Hi,
UCC28910 is being used following the typical application suggestion closely except for one difference: the snubber network on the output side is omitted. The power supply works well without this snubber.
However, if there is a relay placed next to the flyback, the output voltage sometimes jumps from 12V up to 19V. This condition is stable and remains so with full or no load until the power is switched off. The output is then 12V as usual when switched on again.
We have been able to reproduce this effect by generating a strong E-field close to the converter. It seems that the primary side regulation is tricked into locking on to the wrong part of the primary side waveform and stays there.
Would adding the snubber help with this issue? It seems to be some kind of interference issue in the feedback loop.
The effect is not dependent on temperature or input voltage.
Thanks,
Tadeo
