Name: LM2596 DC-DC Buck ModuleInput Voltage: 4V - 35V Output Voltage: 1.23V - 30V Output Source: 3A( Max)Conversion Efficiency: 92%( MAX)Output Ripple: lt; 30mV Switching Frequency: 150KHz Operating Temperature: -Forty-Five-+85Size: 43mm x 21mm x 14mm (L x W x H)Features:1. Input voltage range: 3.2V to 40V dc (the input voltage must be higher than the output voltage of 1.5V above. It can't booster)2. Output voltage range: 1.25V dc to 35V adjustable voltage, high efficiency (92%) the largest maximum output current is 3A. Instructions:1. Power supply (3-40V), power indicator, the module works properly.2. Adjust the blue knob of the potentiometer (clockwise rotation generally increases, counterclockwise rotation), and reach the multimeter to monitor the output voltage required. Note:Current long hours operation is recommended to be used in less than 2.5A,When adding heat sink (output power 10W above), because it is a step-down module,To ensure a stable output set, keep a minimum difference of 1.5V. Package Included: 1pcs x DC-DC Adjustable Power Converter Module.