TPL5010: Watchdog without WAKE

Carl Senecal1

Part Number: TPL5010

Hi,

I only need a watchdog functionality, I do not case about the WAKE

I'm short in MCU pins, so I want to use the TPL5010 ignoring the WAKE signal

My intent is to issue periodic DONE, which will have a shorter period than the programmed delay to avoid the watchdog to assert the RST signal

Is there a problem to issue a "dead reckoning" DONE signal, independently of the WAKE signal?

over 3 years ago

0 Timothy T over 3 years ago

TI__Mastermind 28550 points

Hello Carl,

I don't see an issue running a DONE signal open loop of the wake.

As for your repeat rate of issuing a DONE, I recommend a period less than "Tip" - 20 ms - 100 ns. Of course you will need to address possible error of "Tip" depending on your implementation.

73,
Timothy

0 Carl Senecal1 over 3 years ago in reply to Timothy T

Prodigy 20 points

Timothy,

"Of course you will need to address possible error of "Tip" depending on your implementation."

Do you refer to the case where my system will not issue the DONE signal within the Tip and reset. (in fact all the purpose of having an external watchdog,)

Or another issues/error that I completely miss !!!!

Carl

0 Lane Boyd over 3 years ago in reply to Carl Senecal1

TI__Genius 16845 points

Hi Carl,

Yes, this is the case you want to avoid (no DONE received, thus the RST pulse is issued).

TPL5010 would require one DONE pulse per Tip, so you might set the DONE to 2x/3x smaller than Tip so that you are guaranteed that at least one DONE pulse during each Tip.

Note the typical timer accuracy of TPL5010 is 1%

Kind regards,
Lane

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TPL5010: Watchdog without WAKE