UCC21540-Q1: How much on-resistance between turn-on during Miller plateau region?

Yoshiki Ochi

Part Number: UCC21540-Q1

Hi team,

Could you tell me how much on-resistance between turn-on during Miller plateau region?

Datasheet says that;

"The output stage pull-up structure features a P-channel MOSFET and an additional pull-up N-channel MOSFET in parallel. The function of the N-channel MOSFET is to provide a boost in the peak-sourcing current, enabling fast turn on. This is accomplished by briefly turning on the N-channel MOSFET during a narrow instant when the output is changing states from low to high."

I would like to know (1) turn-on resistance during Miller plateau region (2) turn-on resistance after plateau region.

Regards,
Ochi

over 3 years ago

0 Krystian Plaskota over 3 years ago

TI__Expert 4065 points

Hi,

The turn on resistance during the miller plateau region is Rnmos || Roh, which is 1.47 || 5 = 1.13 ohms. After the plateau region the on resistance increases to 5 ohms as the internal Rnmos turns off.

Regards,

Krystian

0 Yoshiki Ochi over 3 years ago in reply to Krystian Plaskota

TI__Expert 7585 points

Hi Krystian

Thank you. I understood that s Rnmos || Roh, which is 1.47 || 5 = 1.13 ohms.

By the way, I cannot see the figure you attached. If you attached reference figure to understand that in more detail, could you please re-send it?

Regards,
Ochi

0 Krystian Plaskota over 3 years ago in reply to Yoshiki Ochi

TI__Expert 4065 points

Hi,

This is what the internal pull up structure looks like for reference. It is section 9.3.4 of the datasheet.

Also here is an technote that you can look at which goes over the structure in a little more detail.

www.ti.com/.../slla387a.pdf

Regards,

Krystian

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UCC21540-Q1: How much on-resistance between turn-on during Miller plateau region?