TPSM82903: TPSM82903 SS/TR soft start

wolfgang kopp

Part Number: TPSM82903

Dear TI Community,

it seems that the WEBENCH Designer does not consider the VREF/0.75 factor.

Vref= 0.6/0.75=0.8V

Css=Tss*Iss/Vref

Css=0.24*2.5e-6/0.8=750pF.

WEBENCH calculates 0.24ms with 1nF

Best regards,

Wolfgang

0 Yuchang Zhang over 2 years ago

thanks for feedback, please calculate with 0.75V factor firstly, we need some time to check with model team.

Yuchang

0 wolfgang kopp over 2 years ago in reply to Yuchang Zhang

thanks! Any update on this?

0 Yuchang Zhang over 2 years ago in reply to wolfgang kopp

The model should not cover 0.75V factor, but some time needed if update the model, you can calculate based on datasheet firstly

BTW, what's soft-start time do you need?

Yuchang

0 wolfgang kopp over 2 years ago in reply to Yuchang Zhang

for 1ms ramp we used a 3.3nF cap

+1 Yuchang Zhang over 2 years ago in reply to wolfgang kopp

That's ok, you can move ahead.

Yuchnag

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