LM74670-Q1: How to Calculate Vdrop

Logan Weiss

Part Number: LM74670-Q1

Tool/software:

Hi,

I know this part, during T0 as seen in the datasheet, will introduce a forward voltage drop during charging of the charge pump capacitor Vcap. Is there a way to calculate the expected vdrop?

Thanks!

5 months ago

0 Shiven Dhir 5 months ago

TI__Mastermind 46390 points

Hi Logan,

It is dependent on load current and MOSFET body diode characteristics.

Controller has no control over it.

Regards,

Shiven Dhir

0 Logan Weiss 5 months ago in reply to Shiven Dhir

Prodigy 30 points

Sure that is clear, I guess has TI worked out a closed form equation for this part to actually calculate that number?

0 Shiven Dhir 5 months ago in reply to Logan Weiss

TI__Mastermind 46390 points

Hi Logan,

No, but generally it is enough to make our controller work. (>500mV)

Regards,

Shiven Dhir

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LM74670-Q1: How to Calculate Vdrop