Other Parts Discussed in Thread: TPS3820,
Hi,
I have a question.
Can a RESET pulse caused by a voltage drop be canceled by entering a WDI pulse during the 200ms delay period?
According to D/S
"When the supervising system fails to retrigger the watchdog circuit within the time-out interval, ttout, RESET becomes active for the time period td."
However, I would like to check whether the RESET that occurs due to the voltage drop can be canceled with the WDI pulse.
Earlier, I asked E2E about the unintentional reset of this device.
Afterwards, our customer's evaluations gave me more insight into the condition.
While monitoring VCC with an oscilloscope, no problems occur at all,
so
The unintentional RESET was speculated to be a VCC voltage drop rather than a WDI issue.
I strengthened the decoupling as a countermeasure, but it was not effective.
Since the problem symptom does not occur depending on the connected external device, we decided that it would be difficult to take countermeasures on the TPS3820 board.
In fact, according to the customer's evaluation, if WDI is set to 200ms or less, the problem does not occur, so even if RESET is asserted internally, it is speculated that it may be canceled during the delay period.
Setting WDI to 225ms causes an unintended reset.
Best regards,
Hiroshi
