bypass cap value

nick bernard

i usually place a 1uf cap between vdd and vss on all my SX applications very near the SX28. but i'm out of 1uf caps in that case size (2mm pitch).

can i use 22uf caps in their place?

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Mike Green

You can use a 22uf cap if you also have a 0.1uf cap in parallel with it. The smaller cap bypasses the high frequency noise while the larger one takes care of slower power surges. Often, the 1uf is a compromise that somewhat serves both purposes. At a minimum, I would have a 0.1uf capacitor mounted next to each chip if possible between Vss and Vdd and a larger cap (10uf to 47uf) for the board. Usually if you have an on-board voltage regulator, there's an output capacitor that serves that purpose.

nick bernard

thanks mike.

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