UCC21732: RST/EN recognition time

Nam, Dino

Expert 6445 points

Part Number: UCC21732
Other Parts Discussed in Thread: UCC21750

Dear team,

My customer want to know Min recognition time of RST/EN for Enable and shutdown the device on UCC21732.

At UCC21750 datasheet, we can see the RST/EN pin is pulled low for longer than trstfil(typ600ns) like below.

But UCC21732 datasheet, there is no comment regarding time when low should be maintained like below.

UCC21732 and UCC21750 are family device so I think RST/EN function is same between two device.

If not,please let me know your opinion regarding Min recognition time of RST/EN for Enable and shutdown the device on UCC21732.

Thank you.

over 1 year ago

0 Sasikala Thangam over 1 year ago

TI__Expert 8125 points

Hi Dino,

UCC21732 also has spec for TRSTFIL (Deglitch filter time to reset /FLT )- it is 650nsec typical - its part of the electrical parameters table.

Thanks

sasi

0 Nam, Dino over 1 year ago in reply to Sasikala Thangam

TI__Expert 6445 points

Hello Sasikala,

thank you for your comment.

I know UCC21732 also has spec for TRSTFIL. But when the customer want to just disable and shut down the device during normal operation not reset FLT signal. Is the TRSTFIL needed or not? Please let me know your opinion.

Thank you.

+1 Sasikala Thangam over 1 year ago in reply to Nam, Dino

TI__Expert 8125 points

Hi Dino,

Did you mean using EN to disable output? Yes TRSTFIL time is applicable, only when EN is pulled longer than the deglitch time, it will turn off the output.

But then general output turn on/off is controlled with INP and INN pins. I am curious, why EN pin is used in the system?

Thanks

Sasi

0 Nam, Dino over 1 year ago in reply to Sasikala Thangam

TI__Expert 6445 points

Hello Sasikala,

Thank you for your comment.

The customer would like to use EN signal as a emergency situation.

Thank you.

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UCC21732: RST/EN recognition time