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VCC Capacitor?

  1. Jun 5, 2012 #1
    I feel like I know the answer to my question, I am just having a lot of difficulty putting it into words. The questions is the following:

    I have a BLDC driver chip that has a pinout called PBAT and a pinout called VCC. The PBAT is tied to 12V and the VCC is tied to a 2.2uF cap. Now, my understanding is that the PBAT 12V powers the 3 phase driver of the BLDC whereas the VCC (usually tied to 5V) would power the onboard microprocessor. However, because the micro is not being used, VCC is instead tied to the cap. What is the capacitor called (i.e. charge pump)? What exactly is it doing? I am assuming it's preventing something, but like I said earlier I can't put it into words. Any quick explanation would be great.
  2. jcsd
  3. Jun 5, 2012 #2
    Can you give the part number or better yet a link to the datasheet?
  4. Jun 5, 2012 #3
    Yep, sorry, probably should have done that in the first place.


    I am thinking the term is bypass capacitor. But still, an explanation would be great.
  5. Jun 7, 2012 #4
    It is still confusing because you are not specific when you say

    What cap is it tied to, and what end of the cap (what node)? If you can explain that or if you have a schematic of what you're talking about, I think you can get someone to help you.
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