Pololu Magnetic Encoder Pair Kit for Micro Metal Gearmotors (12 CPR, 2.7–18V)

Upgrade your Micro Metal Gearmotor into a closed-loop drive system. The Pololu Magnetic Encoder Pair Kit adds quadrature encoder feedback using a magnetic disc + Hall-effect sensors, giving 12 counts per revolution (CPR) of the motor shaft. The outputs are digital and can connect directly to a microcontroller for speed/position control, RPM monitoring, PID tuning, and odometry.

Encoder type: magnetic disc + Hall sensors; quadrature A/B outputs.
Resolution: 12 counts per revolution of the motor shaft (gearbox multiplies counts at the output shaft).
Supply voltage: 2.7V to 18V (digital outputs).
Compatibility: requires Micro Metal Gearmotors with extended back shaft; this version fits HPCB micro metal gearmotors.

Why/Benefits

Accurate feedback for control

Measure speed and direction with quadrature A/B signals.
Great for PID speed control, distance tracking, and consistent turning.
Counts scale with your gear ratio for high effective resolution at the output shaft.

Wide-voltage, MCU-friendly

Sensor supply works from 2.7–18V.
Digital outputs for direct connection to interrupt pins / digital inputs.
Compact form factor that mounts directly on the motor (minimal extra parts).

Technical specifications

Pololu item	Magnetic Encoder Pair Kit for Micro Metal Gearmotors, 12 CPR, 2.7-18V
Encoder type	Magnetic (disc + Hall-effect sensors)
Output	Digital quadrature (A & B)
Resolution	12 CPR (counts per revolution of the motor shaft)
Supply voltage	2.7V to 18V
Motor requirement	Micro Metal Gearmotor with extended back shaft
Connection	2mm pitch through-holes (solder wires/2mm connector)
Includes	2 encoder boards + 2 magnetic discs

Pinout & power notes

Important:

Extended back shaft required — standard Micro Metal Gearmotors without the rear shaft will not work with this kit.
The encoder I/O uses 2mm pitch through-holes — you must solder wires or a 2mm-pitch connector/header.
When pressing the magnet disc onto the shaft, the gap to the sensor board is forgiving as long as the shaft goes fully through the disc.

FAQ

Is this compatible with all Micro Metal Gearmotors?

It requires the extended back shaft version. This #3081 revision is also compatible with the newer HPCB micro metal gearmotors.
How many pulses will I get at the gearbox output shaft?

The encoder is 12 CPR at the motor shaft. Multiply by the gear ratio to estimate counts per revolution at the output shaft.
Do I need special connectors?

This variant uses 2mm pitch through-holes, so you’ll solder wires or a 2mm-pitch connector. If you want plug-in cables, look for the top-entry/side-entry connector variants.
Can I use it with 3.3V or 5V microcontrollers?

The sensors run from 2.7–18V and provide digital outputs, so it’s commonly used with both 3.3V and 5V logic systems (wire appropriately for your controller).

Magnetic Encoder Pair Kit for Micro Metal Gearmotors, 12 CPR, 2.7-18V

Name: Magnetic Encoder Pair Kit for Micro Metal Gearmotors, 12 CPR, 2.7-18V
Brand: circuitrocks
SKU: POL3081
Price: 744.0 PHP
Availability: InStock