TPS7B63-Q1: Watcthdog time of TPS7B63-Q1

takahiko yokota

Mastermind 7135 points

Part Number: TPS7B63-Q1

I have two questions about TPS7B63-Q1.

Does the Vrosc accuracy influence the watchdog time tolerance?

What the influence the watchdog tolerance in table1 comprehend?

Best regards,

Yokota

over 7 years ago

0 Ryan Eslinger over 7 years ago

TI__Guru 55940 points

Hi Yokota,

Yes the Vrosc accuracy is a factor in the watchdog time tolerance. The watchdog tolerance includes all internal sources of inaccuracy including Vrosc but does not include the tolerance of the external Rrosc.

Very Respectfully,
Ryan

0 takahiko yokota over 7 years ago in reply to Ryan Eslinger

Mastermind 7135 points

Hi Ryan-san

Thank you for the reply.

If Vrosc is 0.95V or 1.05V in table1, what does t(WD) change?

Or are there that's the formula or guideline?

Best regards,

Yokota

0 Ryan Eslinger over 7 years ago in reply to takahiko yokota

TI__Guru 55940 points

Hi Yokota-san,

The Vrosc variation ends up causing variation on Irosc. These are included in the Watchdog Period Tolerance already.

Very Respectfully,
Ryan

0 takahiko yokota over 7 years ago in reply to Ryan Eslinger

Mastermind 7135 points

Hi Ryan-san

Thank you for the answer.

Please let me confirm them.

How does Irosc change by Vrosc variation?

(Ex. Vrosc is smaller 1V(typ), is Irosc small?)

Best regards,

Yokota

0 Ryan Eslinger over 7 years ago in reply to takahiko yokota

TI__Guru 55940 points

Hi Yokota-san,

The relationship is Ohm's Law: Vrosc = Rrosc x Irosc. If the voltage is lower than the typical value, the current will also be lower than the typical listed in Table 1.

Very Respectfully,
Ryan

0 takahiko yokota over 7 years ago in reply to Ryan Eslinger

Mastermind 7135 points

Hi Ryan-san

I made a mistake.
Could you tell me the how does watchdog period change by Vrosc variation?

Best regards,
Yokota

0 Ryan Eslinger over 7 years ago in reply to takahiko yokota

TI__Guru 55940 points

Hi Yokota-san,

If Vrosc is lower than the nominal 1 V, then since Vrosc = Rrosc x Irosc, Irosc will be proportionally lower. As you can see in Table 1, the lower Irosc is, the longer the watchdog period is.

Very Respectfully,
Ryan

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TPS7B63-Q1: Watcthdog time of TPS7B63-Q1