3V Micro Metal Gearmotor w/ Encoder & Cable, 37rpm

• Precious metal brushes
• Shaft length 10mm, D-shaped
• Long lifetime, low noise
• Gear ratio 210:1
• Magneic encoder, 2 channels, 7 PPR

This particular DC motor comes with a 1:210 gear ratio and uses 3V nominal power. The gear ratio will not affect the current draw but does change the torque and RPM. See below for the no-load/rated/stall current, RPM, and torque for a range of ratios!

Provide 3V DC (nominal) to the white and red wires - these connect to your motor driver and can be PWM'd for speed adjustment and direction by using an H-bridge.

Connect the black wire to your microcontroller ground pin, and the blue wire to 3-5V DC using whichever voltage your microcontroller uses. Then you can read the hall effect outputs on the yellow and green wires.

Basically, you just want to interrupt on one of the encoder pins, use count the time since the last interrupt, and multiply the count time by 14-counts-per-revolution and the gear ratio.

A mounting bracket for this motor is also available at: https://www.robotshop.com/en/micro-metal-gearmotor-bracket.html