Features of LM2577 3A DC-DC Step UP LED Voltmeter 3-34V to 4-35V Adjustable Boost Converter module :

1. 1.Multiple output regulator.
2. 2.One button to switch input and output voltage display.
3. 3.Power-down memory function.
4. 4.Press the button for 3 seconds can turn OFF/ON the LED display.
5. 5.With wiring terminal.
6. 6.When adjusting the blue potentiometer, please use a multimeter to monitor the voltage
7. 7.Rotating Clockwise can raise the voltage while rotating counterclockwise could lower the voltage
8. When the module output voltage cannot be adjusted (the output voltage is always equal to the input voltage )Please adjust the potentiometer counterclockwise 20 laps (20 turns) or more till it works.