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Tantalums. What is this. •look nicer on boards LOL!
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in bara 6032 size type. in range 47-2,2 uF. its voltage - in BOM file.
general rule for any capacitor at power line - the bigger the better.
so 47uF is better than 22, 22 is better than 10, 10 better than 4,7.
take what you have.
you can take a size on a step less - so it will be 3528.
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There is a thread on the Microchip forum relating to the ESR of tantalum capacitors on the operation of a 70 mips dspic. Apparently, even 1 to 1.5 ohms of ESR was to much to properly decouple the power pins. An ordinary electrolytic with 1/2 the ESR fixed the problem.
I wouldn't worry about the issue on an analog only IB detector, but if a fast processor is on the board, the need for very low ESR needs to be taken into account.
http://www.microchip.com/forums/m966045.aspx
Rick
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Originally posted by eclipse View PostProcessors are best coupled by ceramic caps, 100nf, 10nF or best - combo of few values.
Low ESR caps you could call <0.1R, I'm using Polymer caps which have 0.02-0.03 ohms ESR and won't blow up in my face if I reverse polarity.
Hi Eclipse what combination / type/ value would you suggest for micro's with a clock speed of 32 Mhz and 64 Mhz ? thanks.
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You can use 1 x 100nF, or 100nF + 10nF (X7R - ceramic) type - with short leads as close to power pins as possible,
SMD caps are good for decoupling because of the leads, if it doesn't screw the layout of the board.
Ceramics are good for high frequency decoupling, use polymer caps (or tantal / aluminium electrolytic) for lower frequencies.
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