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  1. #1
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    Splitting plane for negative power supply

    Hi everybody,
    I used op-amp for my project. And supplied with +12 and -12 volts. My PCB will have 4 layers which are TOP (signal layer) ,POWER (internal plane),GROUND(internal plane),BOTTOM (signal layer). When i split the power plane for supply voltages such as +12V, +5V , +3.3V , i confused where to set my -12 power for op-amp supply. Should i set -12V power to POWER plane or GROUND plane and why ?
    Thank you

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  2. #2
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    Re: Splitting plane for negative power supply

    It is entirely your choice. Using internal layers for power and ground is not absolutely essential, it is done for convenience as those nodes generally need connections in lots of places around the board. To some degree they also provide shielding between outer signal layers but if you run your +/- 12V in the same way as signal traces and use decoupling capacitors to ground near your op-amp it should work perfectly well.

    Brian.
    PLEASE - no friends requests or private emails, I simply don't have time to reply to them all.
    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.



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  3. #3
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    Re: Splitting plane for negative power supply

    Thank you so much. I also found that e-book.

    https://books.google.com.tr/books?id...r%20PCB&f=true

    Click image for larger version. 

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