Hello Expert,
We have some issue on the Soft Start pin.
* Error symptoms
1'st : EN1,2 Signal is High.
2'nd : SS Signal is High-Low-High repetition under 1V (SS pin: does not rise above 1V and operates in a triangular wave form with a value between 1V and 0.5V)
At this time, there is no measured voltage on the OVPB pin.
In other words, there is about 0V. Because CSB1 voltage is equal to LV-Port and CSB1 is 0V.
* Debugging
If we removed noise cap. of OVPB, symptoms is cleared.
But, we have to use noise cap. of OVPB because of system noise.
Do you know the root cause and give us guide?
We want to ask to review our schematic privately and please accept friendly. and then we will share it.
* Another Questions
1. What's the max. value of Covpb Cap.?
2. What's the max value of Soft Start Cap.?
Best Regards,
Michael
