TPS3820-Q1: DWI = High when /RESET = Low

Hi Nishie,

When you state "DWI" are you referring to the watchdog timer input, WDI?

For watchdog timer input (WDI), if it is fixed at high or low longer than the time-out period, then a reset will be triggered. When a reset is triggered the watchdog timer is reinitialized.

In your case as long as WDI is fixed at high during a RESET and then resumes normal positive or negative transitions when RESET is not active (when the watchdog is reinitialized) there should be no problem.

Thanks,

Joshua 

Hi Nishie,

Yuta Nishie said:

I'm sorry. My mistake.
DWI means WDI

No worries!

Yuta Nishie said:

>Is it correct that the watchdog timer is reinitialized after td?

Yes that is correct. 

Yuta Nishie said:

->In other words, if it is between td, is it OK to fix WDI= High?

As you stated, it is OK to fix WDI high during delay time, td. Just be aware of the accuracy of the delay time (Section 7.8 Switching Characteristics of datasheet) to ensure normal positive or negative transitions after reinitialization.

Thanks,

Joshua