Current on GPIO Raspberry -

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i'm trying use fan on raspberry. that, connect fan gpio(general-purpose input/output) output , ground. works fine if connect fan vcc +5v (64ma) or +3.3v(46ma) if connect fan random gpio set output, got twitch. checked multimeter , results tension (3.3v)but current low (32ma).

how can increase current on gpio , increase power given fan (via code avoid use of transistor)? can desactivate internal resistor via rpi.gpio?

i assume dont want control speed of fan ,just on/off.

  1. try connecting severa gpio parallel.(also make sure pins configuration same).

  2. check datasheet of processor.most mcu hase several pins support high current (mostly driving led).

3.the best solution adding transistor or relay. note fans tends add electrical noise ,therefor might need add filters.


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