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DRV8800: CP1,CP2,VCP's capacitors.

Part Number: DRV8800

Hi team.

Is there any voltage specifications for CP1, CP2, VCP on DRV8800?

I can't find voltage spec for CP1 and CP2 on datasheet.

And then, could you pls tell me if it can be use 16V or less at VCP ?

In case of NG.

Could you pls tell me why ?

In case of OK.

Is there an effective capacity limit?

I want to use 0201inc capacitor.

Sincerely.

Kengo.

  • Hi Kengo,

    The CP1/CP2 capacitor should be rated for the maximum VBB voltage used.
    The VCP capacitor should be rated for at least 16V.
    This information is available in the Description section of the Pin Functions Table.

    The charge pump operates at ~11V above VM, so the lowest available voltage is 16V.

    The devices typically are checked to operate with a 50% variation of the capacitor value.

    If the DC bias of the 0201 capacitor is within 50% of the recommended value, the 0201 capacitor should work.

    Rick Duncan
    Motor Applications Team

  • In reply to Rick Duncan:

    Hi Rick.
    Thank you so much your quick reply and best answer.

    Sincerely.
    Kengo.
  • In reply to Rick Duncan:

    Hi RIck.

    Could you confirm my understanding is correct?

    The VBB-VCP and CP1-CP2 capacitors should be rated for at least 16V.

    Because the charge pomp drives at ~11V between VBB and VCP/ CP1 and CP2.

    Do you have ideas about a voltage margin for capacitor ?

    Please let me know.Thank you.

    Sincerely.

    Kengo.

  • In reply to Kengo.Y:

    Hi Kengo,

    The VBB-VCP capacitor should be rated for at least 16V.

    The CP1-CP2 capacitor should be rated for at least VBB V. When charged, the voltage across the CP1-CP2 capacitor will be approximately 1 diode less than VBB.

    Capacitor manufacturers can answer questions about voltage margins.

    Rick Duncan
    Motor Applications Team

  • In reply to Rick Duncan:

    Hi Rick.

    Sorry I confused by "at least" meaning.

    In other words, the VBB - VCP capacitor is no problem if it is 16V or more,isn't it ?
    I'll comfirm with capacitor manufacturers about availability for 16V.

    I'll set the CP1-CP2 capacitor over VBB.

    Sincerely.
    Kengo.