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I have a PCB where I placed a 100uF capacitor near the power supply connector, for power filtering. This capacitor is too big so in my next design I want to use two 22uF capacitors.
My question is: should I place them near each other and near the power connector, or place one of them near the power connector and the other one on the oposite side of the PCB, for uniform voltage stabilization?
The PBC is 80mm x 50mm and the power supply connector is near the 50mm left edge.

EDIT: this circuit is a 24V to 3.3V signal converter only using resistors and transistors, no uControllers or ICs. The signals are square waves with max 50Hz.

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    \$\begingroup\$ If the power source is unregulated, first make sure your circuit can handle the increased ripple from reducing the capacitance to 44% of its original value. \$\endgroup\$ – user_1818839 Oct 13 '20 at 11:25
  • \$\begingroup\$ It is powered by a 24V regulated power supply and a 5 meter cable, so I guess the 100yF was overkill. \$\endgroup\$ – Pedro NF Oct 13 '20 at 11:56
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should I place them near each other and near the power connector, or place one of them near the power connector and the other one on the oposite side of the PCB, for uniform voltage stabilization?

Place them where most needed with a view to minimizing circuit-current-loops carrying ripple current or noise current. The ripple/noise might be from the incoming supply or it might be caused by your circuit.

If both phenomena are present then you might wish to apply 100 nF capacitors local to chips or circuits that could generate high frequency noise/ripple and, place the electrolytics close to the incoming supply if there is significant ripple voltage that needs reducing.

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  • \$\begingroup\$ This circuit is a 24V to 3.3V signal converter only using resistors and transistors, no uControllers or ICs.The signals are square waves with max 50Hz. \$\endgroup\$ – Pedro NF Oct 13 '20 at 12:01
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    \$\begingroup\$ @PedroNF my answer remains the same. \$\endgroup\$ – Andy aka Oct 13 '20 at 12:08

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