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Altera_Forum
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15 years ago

Power and ground pin decoupling capacitors

Hello everybody, In the Max II CPLD manual required Power and ground pin decoupling capacitors requirements are stated as follows: Board Decoupling Guidelines: Decoupling require...
Altera_Forum's avatar
Altera_Forum
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15 years ago

I don't have the document here. Probably this is a typo.

Usually you may need a single big capacitor in the 100uF range to decouple power supply in the middle-low frequency range, near the supply source. The capacitors located near device supply pins are 100nF or 10nF and these are for high decoupling frequencies.

Generally speaking, if no further information is given in a component datasheet I use this rule of thumb: a 100nF and a 10nF for each supply pin.