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DRV8350R: DRV8350R power dissipation quesiton

Prodigy 50 points

Replies: 4

Views: 85

Part Number: DRV8350R

Dear Sir

I'm checking the power dissipation of DRV8350 and I have a question about charge pump power dissipation (Pvcp)

in the datasheet equ. 45

Pvcp = Ivcp *(VM+Vdrain)

but the charge pump output power should only be Ivcp*Vvcp

why the charge pump circuit has so much losses?

thanks!

Albert

  • Albert,

    I am looking into this and I will get back to you.

    Regards,

    -Adam

  • In reply to Adam Sidelsky:

    Hi

    Any result?

  • In reply to kuohen chao:

    Kuochen,

    The reason for this equation is because the charge pump supply is both Vdrain and VM. The doubling operation of the charge pump causes increased current so that extra voltage above the main power supply can be generated.

    Regards,

    -Adam

  • In reply to Adam Sidelsky:

    Hi Adam

    the charge pump output gound level shift to  Vdrain

    so the output power should be Ivcp*(Vvcp-Vdrain) ~= Ivcp*VM

    where is the power loss Ivcp*Vdrain?

    is VCP charge pump also work as a linear regulator?

    BR Albert