UCD90120A: Issue with Logical Controlled GPIO

Matteo Palazzo

Part Number: UCD90120A

Hi,

i am using UCD90120a for sequencing enable pins of several DC/DC converters. Tool version is Fusion Digital Power designer v7.1.1.

The sequence starts when GPIO13 is driven high by an external component, after this event, GPIO14 and then GPIO15 are consequently set to 1 in order to enable the related coverters. GPIO13 is defined as GPI instead GPIO14 and GPIO15 are defined as Logic Controlled GPOs and follow very simple logic equations.

The issue is this: seems that GPIO13 rise up (or high state) is not triggered by GPIO14&GPIO15 boolean equation at first event but at next ones. This means that it's necessary to repeat GPIO13 rising edge generation in order to perform sequence correctly.

I have verified boolean equation correctness and GPIO13 voltage value(3.3V)(and rising edge by using both oscilloscope and Fusion design online monitor app but i have found no difference among first rising edge and next ones.

Can you help me? Have you some suggestions?

Thanks

Best Regards

M.P.

over 5 years ago

0 yihe over 5 years ago

TI__Guru 65610 points

Do you mean that when GPIO13 rise up, GPIO14/15 does not follow it until next time GPIO13 changes?

Does GPIO13 rise up after UCD90120A finishes its power up?

Could you provide your project file so that I can review what the problem could be?

Regards

Yihe

0 Matteo Palazzo over 5 years ago in reply to yihe

Prodigy 50 points

azs04xx_UCD90120a_101d.zip

0 Matteo Palazzo over 5 years ago in reply to Matteo Palazzo

Prodigy 50 points

Hi,

thank you for the your quick answer.

Yes exactly, GPIO14/15 don't follow first GPIO13 riseup but only next ones.

This issue appears after UCD90120a power up is finished.

Sure, i have sent you the project file in previous answer. Thank you

I'm looking forward your answer

Regards

Matteo

0 yihe over 5 years ago in reply to Matteo Palazzo

TI__Guru 65610 points

Thank you for the files. From the configuration, GPIO13 is configured as the 5th GPI and GPIO16 is configured as the 6th GPI.

I would suggest swapping the order: configure GPIO13 as the 6th GPI and GPIO16 as the 5th GPI.

After swapping the order, you have to make according changes on the places where use those GPIs to ensure the functions.

Please let me know the results after swapping.

Regards

Yihe

0 Matteo Palazzo over 5 years ago in reply to yihe

Prodigy 50 points

Hi,

thank you very much for the answer. I will perform some tests for stability verifications and i wil notice you.

Can i ask you why this swapping is necessary? Are there some critical positions (in GUI or physical pin) in which GPI/GPIO/GPO can have some problems similar to this one?

Thank you for the help

Regards

Matteo

0 yihe over 5 years ago in reply to Matteo Palazzo

TI__Guru 65610 points

Swapping the order of the GPIs disable the low latency feature of the GPI.

Please refer section 5.9 of

Regards

Yihe

0 Matteo Palazzo over 5 years ago in reply to yihe

Prodigy 50 points

Hi,

thak you very much for the answer and for the support. The solution proposed it's working.

The issue has been solved

Power management

Power management forum

UCD90120A: Issue with Logical Controlled GPIO