Features 1、Control signal input voltage is 3.3V‑24V general, 32 kinds of subdivision accuracy are optional. 2、H‑bridge bipolar constant current drive, input signal high‑speed optocoupler isolation. 3、Built‑in temperature protection and over current protection, automatic half current to reduce heat. 4、Motor noise optimization function, low noise, not easy to disturb the people. 5、Small size, easy to carry and store, convenient to use and with good performance Specification Item Type: Driver Controller Power Supply Voltage: DC 9-42V power supply (12-24V recommended) Current: The output peak current can get 4.0A (suitable for 57, 42 stepper motors of 1.8NM and below) Cooling Method: Natural cooling or forced air cooling. Use Occasion: (1) Do not place it near to other heat-generating equipment, avoid dust, oil, corrosive gas, excessive humidity and strong earthquakes. (2) Combustible gas and conductive dust are prohibited. Humidity: 40-90%RH Vibration: 10-55Hz/0.15mm Storage Temperature: -20-65℃ Package List 1 x Driver Controller