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power scheme for RF circuit board

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robismyname

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scheme rf

I'm working on a power scheme for my RF circuit board. All my RF part are being feed 3Volts from a TI charge pump. The charge pumps VCC is 5 Volts and it outputs 3 Volts.

My original design has a .1uF in series with each resistor. During my design review a really coky and well respected counterpart said that I should implement 10uF and 100uF in parallel with the .01uF cap.

Because I dont know much about bypass cap's except the basics I'm not sure what he was getting at when he said to add the 10 uF and the 100uF in parallel to the .01 caps.

Question:
1) does my original design with only the .01 uF across the 5 K resistors make sense
2) does it make sense to implement the 10uF and the 100uF approach?
3) Is either legitimate?

Please help if you can.........
 

Parallel combination of capacitor requires to have when u want to have higher bandwidth of decoupling/bypassing. And it should change in footprint too along with the capacitor value. lower value should have smaller footprint. But simulate it for the reverse resonance effect of parallel combination.
 

Multiple parallel capacitors with different values are used because real capacitors have a minimum in the impedance. Ideal capacitors would have a flat Z vs. f curve.
3909_01.gif

The chart comes from this article: https://www.analog.com/library/analogdialogue/archives/39-09/layout.html

- If you replace the 5Ω resistors with inductors or chokes or ferrite beads, you might get better filtering.
- As a fallback plan, in case you find that the charge pump generates too much switching noise, you can replace it with a linear regulator.
 

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