DROK LTC1781 100W DC-DC Step Up Converter, 3-32V 3V 5V 12V to 3-35V 5 V 24V Voltage Boost Regulator Board 6A Switching Power Supply Module with LED Voltmeter USB Interface DROK step up converter input voltage range is DC 3-32V, 3-10v can be used for low input voltage application, 6-32v can be used for high input voltage application, can be selected by the jumper on the board. This boost module continuously adjustable output voltage is DC 3-35V, default 19V; max output current is 6A, has high efficiency and little heat, low ripple and stable performance. Application: diy a stabilized power supply, charge your electronic devices, output with usb interface and identification resistor, a single lithium battery can be boosted to 5V to charge your phone; stabilize voltage for solar panel and etc. The step-up transformer is with digital LED display, it can show input or output voltage, vi: input voltage; vo: output voltage. The power supply board has over current protection and short circuit protection(input 15A fuse), safe to use.