UCD9090A: UCD9090A resequence setting for system power up fail

user4943534

Part Number: UCD9090A

Here is my UCD9090A setting for system monitor and sequence. I want UCD reseqence if any power rail fail on system working or system power on.

But I just confirm fault respone for power rail fail and resquence setting works. It still have problem on power on power rail fail.

Does any different setting I misssed for power up fail resequence?

UCD9090A @ PMBus Address 65d Project_Emerald_UCD_test.xml

over 2 years ago

0 Anne Ngo77 over 2 years ago

TI__Genius 9320 points

Hi,

Please check your Sequencing setting -> Sequencing ON timeout action. You current project set to "wait indefinitely". It should be set to "Resequence".

Regards

Anne Ngo

Texas Instruments

0 user4943534 over 2 years ago

Prodigy 50 points

I had tried this setting too, but power on faol resequence still have problem. The GUI monitor information don't show UVP on fail power rail, only show power good fail fault event.

0 Anne Ngo77 over 2 years ago in reply to user4943534

TI__Genius 9320 points

Hi,

What do you mean by faol resequence? What rail, specifically fail to resequence on sequence-timeout on power on?

Device will not report UVF on rail until voltage monitored on rail cross power-good-on.

Regards

Anne Ngo

Texas Instruments

0 user4943534 over 2 years ago in reply to Anne Ngo77

Prodigy 50 points

I try to short 1.2V output to ground during power up sequence. After power up, remove the short but 1.2V always no power output. But other power rails all turn on. In this situation, 1.2V EN drive by UCD asserted but UCD GUI only show 1.2V power good fail but not do resequence. My question is why UCD know 1.2V power good fail but not do resequence.

+1 Anne Ngo77 over 2 years ago in reply to user4943534

TI__Genius 9320 points

Hi,

VCC1V2 rail (rail #6) has no sequence on dependencies => there is no sequence timeout for that rail => Use TON_DELAY and TON_MAX_FAULT_LIMIT to define the time period of when voltage on rail does not ramp up to PG within that time, then fault occurs, AND set the TON_MAX_FAULT responses for to shutdown and resequence (example shown in the below screenshot with U icons).

Your current setting set to wait indefinitely for rail to turn on (TON_MAX_FAULT_LIMIT = 0), and TON_MAX_FAULT responses is set to "Ignore" => No fault and no resequence.