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I’m more inclined with software than hardware, so there may be a simple answer I’ve missed somewhere.

Most of the ICs I’ve been looking at require multiple VCC and VSS pairs such as cortex processors. I have read many posts elsewhere aging that these pins need to be connected and that they need clean power. What I don’t know is how to properly do it. I’m not asking for exact part numbers or the like, I just want a template that I can adjust for as many or few power pins as I need. I’ve been warned against placing multiple voltage regulators in parallel to accomplish this.

Constraint; I want to supply power to the circuit board with a single pair of wires from an appropriate battery pack and then split that power cleanly to the multiple VCC/VSS pins.

Assume required power will be either 3v or 5v

Any equations I will required to determine the correct parts would be nice, but I really need a diagram with indicated repeatable sections.

Jammane
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I think you are confusing multiple pins and multiple supplies.

If a device has 5 Vcc pins and 5 Ground pins, all the Vcc pins should be connected to the same supply, and all the ground pins to the same ground.

If the device has 5 Vcc pins and 2 Vcc_ADC pins, the latter two could be attached directly to the same place as the 5 Vcc pins, or indirectly to there through some additional filtering.

Each and every Vcc pin should also have an associated decoupling capacitor, or capacitors populated and attached as close to the pin as possible. Additional, more complex, filtering can also be added for sensitive circuits or very high frequency devices.

With this type of component, power and ground planes are much preferred as the pins can connect to the appropriate plane very close to the pin for SMT, and right at the pin for through hole.

Related Question

Trevor_G
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  • You may be right about my confussion. On the same note, if I have multiple different chips on the same board would that still hold true. Can I connect VCC from multiple chips of the same voltage like that as well, or would that require the other option? – Jammane Oct 26 '17 at 14:30
  • @Jammane normally everything that needs a certain voltage is powered from the same place yes. Separate supplies for the same voltage are rarely used, except under special design requirements. – Trevor_G Oct 26 '17 at 14:34
  • Can you provide a good place for me to read up on decoupling capacitors? – Jammane Oct 26 '17 at 14:38
  • @Jammane there are literally thousands of pages on that, but here is a half decent one https://learn.sparkfun.com/tutorials/capacitors/application-examples – Trevor_G Oct 26 '17 at 14:40
  • I'd recommend EEVblog for the decoupling caps, Dave nails the subject down pretty well (except not mentioning the anti-resonance). – Mike Oct 26 '17 at 19:10