Data Sheet

current of 3 A (5 A peak) allow this board to control most small DC brushed motors. Analog
voltage and tachometer (frequency) feedback options allow quick implementation of closed-
loop servo systems, and a free configuration utility (for Windows 7, Vista, or Windows XP)
allows easy calibration and configuration through the USB port.
Key improvements over competing products and earlier Pololu motor controllers with
feedback include:
• USB connectivity with emulated serial (COM) port allows direct motor control from a
PC.
• Ultrasonic PWM to eliminate switching-induced motor shaft hum or whine.
• Robust, high-speed communication protocol with user-configurable error condition
response.
• High internal resolution (12 bits) for smooth and flexible calibration to various input and
feedback devices.
• Current sensing and limiting.
• Reversed power protection.
• Field-upgradeable firmware.
Note: A USB A to mini-B cable (not included) is required to connect this controller to a
computer
Main Features of the Jrk 21v3
Simple bidirectional control of one DC brush motor.
• 5 V to 28 V operating supply range.
• 3 A maximum continuous current output (5 A peak).
• Four communication or control options:
1. USB interface for direct connection to a PC.
2. Full-duplex, TTL-level asynchronous serial interface for direct connection to
microcontrollers or other embedded controllers.
3. Hobby radio control (RC) pulse width interface for direct connection to an RC
receiver or RC servo controller.