UCC28700: RLC in PMP10276

tateo yamashiro

Part Number: UCC28700
Other Parts Discussed in Thread: PMP10276

Hi,

We got a question from the customer about UCC28700.
Could you help us?

[Question]
- They calculated RLC based on schematics of PMP10276 and the result is 51.1k. But RLC is used 698ohm in PMP10276. Why is chosen RLC much smaller than calculated result?

Best Regards,
tateo

over 6 years ago

0 John Stevens over 6 years ago

TI__Expert 7395 points

Tateo,

Thanks for the interest here. I'll contact the designer if that reference board and they can explain their selection.

Regards

John

0 tateo yamashiro over 6 years ago in reply to John Stevens

Guru 10890 points

Hi, Thank you for your reply. We look forward to your feedback.

Best Regards,

tateo

0 Sheng-yang Yu1 over 6 years ago

TI__Expert 4370 points

Hi,

The RLC calculation is based on equation 3 in the datasheet, which is RLC=[KLC*RS1*RCS*tD*NPA]/Lp.

With KLC=25, Rs1=75kohm, RCS=0.375, tD=50nS, NPA=40/11, Lp=250uH, the calculated RLC is 511.364ohm, which is closed to 698ohm used in this design.

Regards,
Sheng-Yang Yu

0 tateo yamashiro over 6 years ago in reply to Sheng-yang Yu1

Guru 10890 points

Hi, Sorry, We made a mistake. Thank you for your support.

Best Regards,

tateo

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UCC28700: RLC in PMP10276