UCC27324: Behavior change

Andres B.

Part Number: UCC27324

Tool/software:

I have a question regarding the UCC27324DR component. When measuring the internal impedance (using a multimeter in resistance mode) of older components (e.g., DC 2118), the measurement show approximately 107K. However, with newer components (e.g., DC 2438), the internal lines appear open. Please confirm if this behavior is correct.

24 days ago

0 Amy Wozniak 24 days ago

TI__Intellectual 1115 points

Hi Andres,

Could you clarify what you mean by internal impedance? Between which pins are you measuring this?

Best,

Amy

0 Andres B. 23 days ago in reply to Amy Wozniak

Prodigy 20 points

Hello Amy,

We are measuring the DC resistance from each output pin to GND.

0 Annabelle Alemand 23 days ago in reply to Andres B.

TI__Intellectual 790 points

Hi Andres,

The UCC27324 underwent a product change notification (PCN) over a year ago. The device was requalified, leading to some changes in the electrical characteristics.

Could you please provide images of the topside markings of the packages of the older and newer component so we can confirm the device versions? Once we have those, we will run a quick bench test to determine if what you are seeing is accurate to the PCN.

Thanks,

Annabelle

0 Andres B. 22 days ago in reply to Annabelle Alemand

Prodigy 20 points

Hello Annabelle,

Kindly see below.

Marking newer components:

Marking older components:

Thanks

0 Annabelle Alemand 22 days ago in reply to Andres B.

TI__Intellectual 790 points

Andres,

Thank you for the images. I will test the pre- vs post-PCN output resistance and get back to you with the results, hopefully by early next week.

Thanks,

Annabelle

+1 Annabelle Alemand 18 days ago in reply to Annabelle Alemand

TI__Intellectual 790 points

Hi Andres,

Thank you for your patience. Here are the results from bench testing pre- vs post-PCN.

UCC27324 Pre-PCN

OUT to GND Resistance

UCC27324 Post-PCN

OUT to GND Resistance

106.77 kOhm

1.97 MOhm

Thanks,

Annabelle

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UCC27324: Behavior change