I recently purchased some a Micro Coreless Motor in hopes of getting motor that can be controlled without having to add extra power to the micro:bit. It’s a 4.5V motor, but I saw several demos of it running off of a single CR2032 battery. They are tiny (4mmx8mm) and take up only 0.12A. When I hook it up to the micro:bit’s 3V pin, it starts running immediately. However, if I hook it up to the 0, 1, or 2 pins (using the same alligator clips), and send a digital signal of 1, the motor won’t do a thing. What’s the reason that the motor can run off 3V and not one of the other ports?
Hi @drrich — Welcome to the forum!
Please see the response in this post: Motor not spinning . Summary: It’s probably a power problem. The output pins are limited to about 15 milliamps (0.015A — about 1/10th of the 0.12A you mentioned). That post includes a link to an example circuit using Elecfreak’s Micro:bit Starter kit. The circuit uses the output pin to control a transistor and the transistor is capable of higher current that the motor needs.
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