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Hannover, Germany
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Hi all,

I'm getting old  smiley-wink I forgot the proper way, and the search of these words gives too much results. I want to drive two leds with one PWM output pin (left eye and right eye of my evil spider  smiley-evil). Serial or parallel? (For the latter: one or two resistors?).

best regards
Andreas
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If the forward voltage is low enough --> serial. If it is to high --> parallel with separate resistors.
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Hannover, Germany
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Brett vorm Kopf (plank in front of head  smiley). Standard LED, U_F = 2.25 V; this gives the forward voltage of 4.5 V. So: 5 V - 4.5 V = 0.5 V; R = U/ I is here R = 0.5V / 10 mA = 50 Ohm. Is this correct? (Just to be sure).

Thanks, Danke, merci, gracie
Andreas
« Last Edit: April 13, 2012, 11:47:49 am by danimath » Logged

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Quote
Is this correct?
Yes  smiley
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Hannover, Germany
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Thanks, Danke, merci, gracie Mike! I've done this stuff 40 years ago, so the knowledge got a little bit rusty  smiley-wink

Andreas
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