UCD9081EVM: enable active high vs active low

Sean Rauchfuss

Part Number: UCD9081EVM
Other Parts Discussed in Thread: UCD9081

Posting for a customer:

We have a design using the UCD9081. A short program was created using the EVM SW which would set an active high Enable when the monitor input is 1.1v. The behavior we see in the lab is that the active low box needs to be checked in order to get the enable 1 output to go high. Below is the circuit and program. Can you shed some light on why this seems to be working opposite to what we would expect?

Thank you!

over 7 years ago

0 yihe over 7 years ago

TI__Guru 60800 points

Could you please provide the complete configure file? does the configure file work expected on TI 9081 EVM?
Thanks
Yihe

0 Sean Rauchfuss over 7 years ago in reply to yihe

TI__Intellectual 935 points

Yihe,

I just emailed you the par file internally.

The configuration file did not work until the “active Low” check box was selected. The Enable was measured as a high output which turned on the LED.

Thanks,
Sean

0 yihe over 7 years ago in reply to Sean Rauchfuss

TI__Guru 60800 points

Hi Sean
When None is selected for Sequencing condition, it means that the rail shall not start at all, therefore the EN output is reversed of what configured to prevent the accidently turn on the rail. If customer wants to turn on the rail, None shall not be used at all, it shalluse other three settings for Sequencing Conditions.
Hope this help your customers.
Thanks
Yihe

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UCD9081EVM: enable active high vs active low