Resistors and physical computing. - Raspberry Pi Forums

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hello. absolute beginner when come physical computing. have bought rpi starter kit of electrical components ebay. has 220, 1k , 10k ohm resistors. of led projects i've seen use 330 ohm. damage pi if use 220 ohm? can recommend beginners site learn electronics, more breadboard. have googled there many it's confusing. thanks.

no 220 ohms won't damage it, maybe bit brighter. may limit number of leds can light @ once total limit gpio's quoted 50 ma. put 2 in series 440ohms, little less bright.

if led has vf of 2v then
(3.3-2)/330 = 3.9ma,
(3.3-2)/220 = 5.9ma
(3.3-2)/440 = 3.0ma

gordon


raspberrypi



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