SMAKN&reg; New DC-DC LM2577 Adjustable Step-up Power Supply Module 3.5-30v to 4-30v Dc Power Regulator Boost Voltage Converter *Wide Input voltage: 3V-30V Output Voltage: 4-35V (Adjustable) Output current: rated current 3A MAX ( Heat-sink Needed) If you need its output power greater than 15W, please add with heat-sink Conversion efficiency: Up to 92% (output voltage higher, the higher the efficiency)