Choosing the right diode for the situation

[vipulan12]

Hey guys I have this motor I want to use for my arduino but I don't want to destroy my arduino because of the reverse voltage the motor will produce

so how do I choose the right diode for the situation and  How exactly would I calculate this?

just in case your wonder where i got this motor from
 -I got the motor from the rc car that tonka made but its fairly old
 -I tried to see if i could reuse any diodes in the circuit but I couldn't find any anywhere
 -the car runs on 4 double AA batteries

[Soeren]

Hi,

Hey guys I have this motor I want to use for my arduino but I don't want to destroy my arduino because of the reverse voltage the motor will produce

You're not trying to conect a motor directly to an I/O pin on the Arduino I hope?

so how do I choose the right diode for the situation and  How exactly would I calculate this?

Diodes are not calculated, but chosen for the pararmeters you have.

-I got the motor from the rc car that tonka made but its fairly old
 -I tried to see if i could reuse any diodes in the circuit but I couldn't find any anywhere
 -the car runs on 4 double AA batteries

We could try to calculate how fast you'd ruin your Arduino if you connect it directly, but it'd probably be less than 1ms, so do we bother 

You need a motor driver in-between and that is what you protect with diodes.
To find out what power handling is needed from the driver, you need to measure your motor.

[vipulan12]

but why not,

what's wrong with connecting the motor directly to the arduino (with diodes)? 

and what does the motor controller do exactly(how does it generally works?

[vipulan12]

sorry not motor controller but motor driver(is there a difference?)

[Soeren]

Hi,

but why not,

what's wrong with connecting the motor directly to the arduino (with diodes)? 

You destroy the microcontroller in the Arduino, either fully or "just" one (or more) I/O pins.

and what does the motor controller do exactly(how does it generally works?

It takes a low current in and gives a higher current out.

sorry not motor controller but motor driver(is there a difference?)

A motor driver is just a current amplifier, while a motor controller implies that there's some kind of logic circuitry (perhaps a microcontroller) involved, but sometimes they get mixed up.


Please use "Modify" rather than serial posting!

And please start reading some basic electronics tutorials (Google is your friend) - you'd be able to answer most of your questions here yourself with just a little bit of reading.

[jkerns]

Read the specifications on your Arduino - pay particularly close attention to how much current the I/O pins can handle. Compare that to how much current you motor will be using. You can't put 0.5  pounds in a bag that only holds 0.02 pounds.