hiBCTR 2-Piece 15W DC-DC Buck Boost Voltage Converter, 5V to 3.3V 9V 12V 24V 30V CVCC Step Up/Down Module Adjustable USB Power Supply Module with Shell.

Adjustable output voltage The adjustable USB boost power module can be used as a USB - input adjustable desktop power supply. The output voltage can be adjusted arbitrarily within the range of 0 - 2A (wide input 4 - 13V, wide output 0.5 - 30V, with short - circuit protection, and short - circuit won't cause burning). ^^ Safe operation When used as a USB charging cable, the charging voltage and maximum charging current can be adjusted arbitrarily (any voltage, constant current, anti - backflow, and can meet the charging needs of most batteries).

^^ Three input power modes
Input 1: Standard type A USB male head. It can only input DC 5V.
Input 2: Micro USB female head. It can only input DC 5V.
Input 3: IN + and IN - welding pads. It can input DC 4.0V - 13.0V. When using the welding pads for input, be careful not to connect the positive and negative electrodes reversely, and do not connect AC power. ^^ Multiple protection functions It has short - circuit, over - current, over - heat, over - power, over - voltage protection, and charging anti - backflow protection. ^^ Wide range of applications It is widely used in general power supplies, battery chargers, LED - driven power supply, instrument voltage display, test counter, circuit testing, and power conversion. For more details, please read the user manual (not necessarily in Chinese).