Hi Team,
My customer is testing our TPS51116, when they do the Damped shock immunity test on the board. TPS51116 will restart when doing the test, below is the schematic and related components parameters:
When doing more test, it was found that it seems the L32 was disturbed, if they shield the L32, the circuit works normally when doing the Damped shock immunity test. Once the shield was moved, TPS51116 will restart. On the same time, if we take the shield away, we found that if we change the R465(Rtrip) from 4.7kohm to 20kohm, TPS51116 will work but when doing the Damped shock immunity test, these is no any improvement. When change the R465 from 20kohm to 30kohm, TPS51116 can't work even we didn't do the Damped shock immunity test. When change the R465 to 1kohm, when doing the Damped shock immunity test, it seems TPS51116 works well and it seems the anti-interference ability was improved. So here comes questions and customer ask for solution to solve:
1. Why TPS51116 can't work with R465=30kohm?
2. Why with R465=1kohm, it seems the anti-interference ability was improved, this is not quite in line with our knowledge because we think with bigger Rtrip, the
IOCP should be bigger, then the anti-interference ability should be improved.???
3. Do you have some suggestions to solve the issue?
This is very urgent, need team's great support on this, thanks a lot!
Best regards,
Sulyn Zhang
