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Author Topic: Home built microcontroller - capacitor question  (Read 343 times)
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Hi everyone,
I am in the process of assembling a homebuilt microcontroller, the schematics are calling for 22pf capacitors x2,but I don't have any. I have a ton of capacitors (mylar and disk) and am wondering if I can substitute the 22's with something else.
Any help on this matter is most appreciated.
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Those capacitors are probably connected to the crystal. Anything between 10pF and 30pF will probably work. You may get away omitting those capacitors completely, but I wouldn't recommend it, other than as a stopgap while you order the capacitors. You could try using two pieces of insulated solid-core wire twisted together.
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Only something that is in the same range - 18-27pF.

Could leave them off until you get some. Get some extra, prep for your next project:

http://www.dipmicro.com/store/C1K27-50
http://www.taydaelectronics.com/capacitors/ceramic-disc-capacitors/10-x-22pf-50v-ceramic-disc-capacitor-pkg-of-10.html
http://www.digikey.com/product-detail/en/C317C220J2G5TA/399-4220-ND/817996
http://www.mouser.com/ProductDetail/Xicon/140-50N5-220J-RC/?qs=sGAEpiMZZMuMW9TJLBQkXrAu%2ft0BXINgpxwL83GinRY%3d
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Ok. Thanks for the help.
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I had the same but with ebay I just ordered 50 of them for 99p
I only need 3 but as it was cheaper to bulk them I now have spares.
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Sorry for the noobish post but my knowledge is 10 years out of date!

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