DC-DC Boost Converter, Power Supply Step Up Module with Voltmeter, Adjustable Boost Converter 4.5V-32V Input 5V-35V Output

Specifications: Input Voltage: 4.5V-32V Output Voltage: 5V-35V (adjustable) Max. Output Current: 4A Efficiency: <92% Output Ripple: <30mV Switch Frequency: 400kHz Operating Temperature: -40?~+85? Size: 66*36*14mm/2.59*1.41*0.55" Instruction: 1. For the first time powering on, the default display is input voltage, and the input indicator IN lights up.Press the button, then it displays output voltage, and the output indicator OUT lights up.The last setting will be saved, even if power off and restart. 2. Input output voltage measurement error calibration:Press and hold button switch for more than 4 seconds then release to enter voltage measurement error calibration function, indicator IN lights up(input voltage calibration), and display flickeringly shows calibration value (default is 0.0). Press button to change this value (range of -0.5V to 0.5V)After adjustment of the input voltage calibration value, press and hold button for more than 2 second then release to enter the output voltage error calibration function, indicator OUT lights up (output voltage calibration), and display calibration value. Adjustment method is the same as the input adjustment.  1. If input voltage is lower than 4.5V, the voltmeter will not work and display. 2. Input voltage must be at least 1V higher than output voltage. 3. When power is over 20W, a heat sink is recommended to enhance heat dissipation. 4. If output voltage is always equals to input voltage and cannot be adjusted,turn potentiometer more than 10 circles counterclockwise please, then voltage can be adjusted normally. Package Includes: 1 x Boost Converter Module