The N20 Miniature Metal Gear Motor with Dual-Channel Hall Effect Quadrature Encoder (6V / 200 RPM / 10mm D-Shaft) is an all-in-one, high-precision DC micro gear motor engineered for closed-loop speed control, accurate odometry, and angular positioning in compact robotic systems. Combining a miniature brushed DC motor core with an all-metal micro spur gearbox and a rear-mounted magnetic Hall-effect quadrature encoder PCB, it delivers high output torque and low-speed stability while providing 2-channel quadrature pulse feedback. With a standardized 3mm D-shaped output shaft extending 10mm and an ultra-compact form factor, this motor is widely utilized in micro robotics, balance bots, smart toy vehicles, 2WD/4WD mini rovers, automated locks, electronic measurement devices, and medical actuator mechanisms.

Specifications

• Motor Model / Type: GA12-N20 Micro DC Gear Motor with Magnetic Encoder
• Rated Operating Voltage: 6.0 V DC (Operating Range: 3.0V to 9.0V DC)
• No-Load Output Speed: Approx. 200 RPM (±10% at 6.0V DC)
• No-Load Current: ≤ 60 mA (Typ. 40 mA to 50 mA at 6.0V)
• Rated Load Speed: Approx. 150 to 160 RPM
• Rated Load Current: ≤ 150 mA
• Rated Load Torque: Approx. 0.3 kg·cm (0.03 N·m / 4.2 oz-in)
• Stall Torque: Approx. 1.2 kg·cm to 1.6 kg·cm (0.12 N·m to 0.16 N·m)
• Stall Current: Approx. 600 mA to 750 mA (at 6.0V DC)
• Gearbox Type: All-Metal Micro Spur Reduction Gearbox
• Gear Reduction Ratio: Approx. 1:50 to 1:100 (Nominal for ~200 RPM @ 6V)
• Encoder Specifications:
  • Encoder Type: Dual-Channel Incremental Magnetic Hall Effect Quadrature Encoder
  • Encoder Operating Voltage (VCC): 3.3 V to 5.0 V DC
  • Signal Output Format: 2-Channel Square Wave (Channel A & Channel B with 90° Phase Offset)
  • Base Pulse Count (CPR): Typically 3 to 7 Pulses Per Revolution (PPR) per channel at the raw motor shaft
  • Output Resolution (PPR at Output Shaft): CPR × Gear Ratio (Provides hundreds of quadrature counts per revolution for fine odometry)
• Output Shaft Specifications:
  • Shaft Type: Single Flat D-Shaft (D-Cut for secure wheel/gear hub fastening)
  • Shaft Diameter: 3.0 mm (D-Cut flat thickness approx. 2.5 mm)
  • Shaft Length: 10.0 mm (Usable extension from gearbox faceplate)
• Interface Connector: 6-Pin Micro JST-ZH (1.5mm pitch) or Solder-Pad Ribbon Lead
• Operating Ambient Temperature: -10°C to +60°C
• Overall Dimensions: Approx. 12 mm × 10 mm × 38 mm to 40 mm (Excluding output shaft; Total length approx. 50 mm)
• Net Weight: Approx. 14 g to 16 g

Wiring Pinout (Standard 6-Wire Interface)

• Red (M+ / Motor +): Motor Power Supply (+3V to +9V DC; PWM drive input)
• Black (M- / Motor -): Motor Power Ground / Return (Swap with Red to reverse rotation direction)
• Blue (VCC): Encoder Logic Power Supply (+3.3V or +5.0V DC)
• Green (GND): Encoder Ground (0V / Common Ground with microcontroller)
• Yellow (Phase A / OUT_A): Hall Sensor Channel A Digital Output (Square Wave)
• White (Phase B / OUT_B): Hall Sensor Channel B Digital Output (Square Wave, 90° out of phase)

Features

• Dual-Channel Quadrature Feedback: 90° phase-shifted Channel A and B outputs allow microcontroller timers/interrupts to determine both high-precision rotational speed and direction of rotation.
• Rugged All-Metal Gearbox: Heavy-duty brass and steel spur gears offer high durability, low backlash, and strong resistance to gear stripping under stall or shock loads.
• Micro-Compact Form Factor: Standard 12mm × 10mm cross-section fits into extremely tight spaces inside miniature robot chassis and handheld devices.
• D-Shaped 10mm Drive Shaft: Ensures non-slip mounting for wheels, pulleys, couplings, and robotic linkages using standard M3 set screws.
• Low Power Consumption: Highly efficient core delivers smooth torque with minimal quiescent and loaded current draw, ideal for Li-ion battery-powered setups.

Common Applications

• Miniature Robotics & Rovers: Micro 2WD/4WD wheeled mobile robots, line-tracking bots, and micromouse maze runners requiring precise wheel odometry.
• Self-Balancing Micro Bots: Real-time PID speed and angle stabilization using high-speed quadrature encoder feedback.
• Automated Locking & Access Systems: Smart deadbolts, safe locks, and electronic latch actuators.
• Pan-Tilt & Camera Gimbals: Precise low-speed positioning for miniature security cameras and optical tracking mounts.
• Laboratory & Medical Devices: Miniature peristaltic pumps, syringe drivers, and motorized fluid valves.

Usage Tips

• Motor Driver Selection: Drive the motor power lines (Red/Black) using an H-Bridge motor driver (such as the DRV8833, TB6612FNG, or L298N). Do not attempt to power the motor coils directly from microcontroller GPIO pins.
• Encoder Supply Voltage: Power the encoder logic (VCC / Blue) with 3.3V or 5V matching your microcontroller logic level. Ensure the Green (GND) wire shares a common ground with both the motor driver power supply and the microcontroller.
• Microcontroller Interfacing: Connect Phase A (Yellow) and Phase B (White) directly to Hardware Interrupt-capable GPIO pins on your microcontroller (e.g., Arduino, ESP32, STM32, or Raspberry Pi Pico) to capture quadrature pulses using internal encoder counters without missing counts.
• Direction Decoding Logic: When rotating forward, Phase A leads Phase B. When rotating in reverse, Phase B leads Phase A. Checking the state of Phase B inside the Phase A rising-edge interrupt service routine (ISR) provides instantaneous direction tracking.
• Avoid Sustained Stalling: While the all-metal gearbox is rugged, sustained mechanical stalling at full 6V power can cause thermal degradation of the brushed core or accelerate gear wear. Implement software overcurrent protection or current monitoring.