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I'm trying to use a fan on my raspberry. To do that, I connect my fan to a GPIO(General-purpose input/output) output and the ground. It works fine if I connect the fan to VCC +5V (64mA) or +3.3V(46mA) but if i connect my fan to a random GPIO set as an output, I got just a twitch. I checked with a multimeter and it results that my tension is good (3.3V)but the current is too low (32mA).

How can I increase the current on this GPIO and so increase the power given to the fan (via a code to avoid the use of a transistor)? Can I desactivate the internal resistor via RPi.GPIO?

Kara
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psyked
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    GPIO are logic pins, not power pins. Use a relay or electronic equivalent. You need to learn the basics of electricity; seems like you're unaware of voltage. *"my current is good (3.3V)"* -- Current is not measured in volts. *"the intensity (32mA)"* -- There's no such thing as electrical *"intensity"*. – sawdust Jul 21 '16 at 01:55
  • A GPIO pin at its upstate works as a VCC (+ resistor) so yeah it delivers power ... But it's the "+ resistor" the problem and I need to disable this internal resistor to get rid of the transistor i use. – psyked Jul 28 '16 at 14:07

1 Answers1

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I assume you dont want to control the speed of the fan ,just ON/OFF.

  1. Try connecting severa GPIO parallel.(also make sure pins configuration is the same).

  2. Check datasheet of the processor.most MCU hase several pins that support high current (mostly for driving LED).

3.The best solution adding transistor or relay. Also note that fans tends to add electrical noise ,therefor you might need to add filters.

Oren Fivlovich
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