Let's Make Robots!

letsmakerobots - motor is not spinning

i have created the simple circuit using breadboard to blink led every 5 sec using microcontroller.

it works well and the led flashes out for 5 sec.

i want to use motor in the circuit.

but if i place the motor in place of led,the motor does not spin.

is the enough current not passing from microcontroller to motor or i have to use additional components like transistor/mosfets etc.

however if i connect the motor to 1.5 v cell battery separately,it spins well.

Can you help me what could be the reason the motor is not spinning ?

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

If you are lucky, you have not damaged your chip. You will need at a bare minimum a transistor circuit capable of handling your motor's current demand. For example, a smallish dc motor will require say a minimum of 50mA. Your microcontroller pins can, at best, offer 40mA.

If you could/would, please put the LED back in the circuit on the same pin and let us know if it still blinks.

See this: http://www.oomlout.com/oom.php/products/ardx/circ-03

It contains a set-up tutorial to run a motor from an Arduino for beginners. I think there's one problem in the schematic though - you don't need the resistor that goes to Pin 9.

This is the transistor the tutorial suggests:


... I'm just wondering what it is in the datasheet that says it is appropriate to boost the current to an acceptable level (is it the 600mA Collector Current)?