Elecrow stepper motor HAT (dual A4988): specs and pinout
Elecrow's Stepper Motor HAT for Raspberry Pi: an I2C motor-driver board with four H-bridge motor outputs (M1 to M4) that can drive four DC motors or two stepper motors, plus four servo headers and 16 PWM channels. Elecrow's own documents describe H-bridge outputs and do not mention A4988 drivers.
Specs
| Spec | Value | Source |
|---|---|---|
| Motor outputs | 4 H-bridges: 4 DC motors (M1 to M4) or 2 stepper motors (M1+M2 and M3+M4) | source Details; Features |
| Current per output | 1.2 A per bridge, 3 A peak, with thermal shutdown and internal kickback protection diodes; not for continuous loads over 1.2 A | source Features; guide: Using DC Motors |
| Motor supply | 5 V to 12 V DC on the Power terminal block, polarity protected; the HAT does not power the Raspberry Pi | source Powering Motors; Power it up; Specifications |
| Interface | I2C; default address 0x6F; the I2C connector is rated for 3.3 V or 5 V | source Using DC Motors (address); Features |
| PWM | 16 PWM channels, 12-bit resolution, up to 1.6 kHz | source Features |
| Servo headers | 4 servo headers on channels 0, 1, 14 and 15 (3-pin) | source Connecting a Servo; Details |
| Size and weight | 65 x 56 x 21 mm; 20 g | source Specifications |
| Compatibility | Elecrow says it is aimed at Raspberry Pi model A+, B+ or Pi 2 | source Features |
Power
| Value | Source | |
|---|---|---|
| Supply | 5 V to 12 V DC for the motors on the Power terminal block (separate from the Raspberry Pi's own supply) | source Powering Motors; Power it up; current limit 1.2 A per motor, 3 A peak |
Pinout
The rows are the board's terminals and headers as named in Elecrow's user guide and product page, not a 40-pin GPIO map. Elecrow does not publish which Raspberry Pi GPIO pins the HAT uses beyond I2C.
| Pin | Function | Voltage | Notes | Source |
|---|---|---|---|---|
| M1, M2, M3, M4 | Motor terminals (DC motor on one terminal pair; a stepper uses M1+M2 or M3+M4) | Motor supply 5 V to 12 V | Bipolar and unipolar steppers use the same library calls; unipolar centre taps go to the GND terminal | source Connecting DC Motors; Connecting Stepper Motors |
| Power terminal block | Motor supply input | 5 V to 12 V | Polarity protected; an LED lights when polarity is correct | source Power it up |
| Servo headers 0, 1, 14, 15 | 3-pin servo connectors (signal on the top row, ground on the bottom row) | The guide does not state the header voltage | source Connecting a Servo | |
| I2C connector | I2C control, default address 0x6F | 3.3 V or 5 V | Compatible with 3.3 V and 5 V hosts | source Features; Details |
Build with it
Project ideas for the Elecrow stepper motor HAT (dual A4988). Each link opens Soldr with the prompt filled in; Soldr assigns the pins, checks power and shows how to wire every part.
- Two-motor robot base: Two motors on M1 and M2 with PWM speed control (0 to 255). A fresh 4 x AA pack is about 6.4 V, inside the HAT's 5 V to 12 V range, and the Pi uses its own supply as the guide advises. Use this only if the motor is rated 1.2 A or less (its stall current is not published here), run one motor at a time while testing and keep runs short. Elecrow names Pi A+, B+ and Pi 2; Pi 4 support is not confirmed by Elecrow.
- Pan-tilt camera mount: The HAT has servo headers on channels 0 and 1. Its guide does not state the header voltage, so measure it with the 4 x AA pack connected before plugging a servo in; the MG90S rating is on its own page. Tell anyone who can be in view and get consent. Run one servo at a time; the 4 x AA pack also feeds the servo headers, whose voltage Elecrow does not publish. Elecrow names Pi A+, B+ and Pi 2; Pi 4 support is not confirmed by Elecrow.
- Product photo turntable: One motor on M1 turns the platform; PWM speed control lets you slow it well below the motor's nominal speed. Keep the load light so the motor stays inside the HAT's 1.2 A limit. Use the motor only if it is rated 1.2 A or less. Elecrow names Pi A+, B+ and Pi 2; Pi 4 support is not confirmed by Elecrow.
Common mistakes
- Powering the Raspberry Pi from the motor supply: the HAT does not power the Pi, and Elecrow strongly recommends two separate supplies because motors put noise on a supply (source: link, Power it up).
- Running motors above the driver's limit: the H-bridges are rated 1.2 A continuous and 3 A peak, a small DC motor can draw up to 3 A when stalled, and near 2 A the guide advises a heat sink (source: link, Powering Motors; Using DC Motors).
- Assuming DC motors stop when the Python script ends: the PWM driver keeps running, so release all motors in an exit handler (source: link, DC motor control).
Not covered by the official source
- Elecrow gives no motor driver chip name, no GPIO map beyond I2C, and no servo-header voltage.
- The guide's software steps are for older Raspberry Pi models; Elecrow's product page names model A+, B+ or Pi 2, so support on a Pi 4 is not confirmed by Elecrow.
- No stepper motor in the parts list has a published current of 1.2 A or less, so no stepper idea is given.
- The product page feature list also says 6 V to 12 V for the stepper and gear motors while other lines say 5 V to 12 V; this page uses the guide's 5 V to 12 V.