SainSmart LM2596 DC-DC Buck Converter Step Down Module Power Supply 1.23V-30V Powered by SainSmart advanced technology Input: DC 3-40V (input voltage must be higher than the output voltage to 1.5v above can not boost) Output: DC 1.5-35V voltage continuously adjustable, high-efficiency maximum output current of 3A. All SANYO solid capacitors, the 36u thickening circuit boards, high-Q inductance Dimensions: 45 (L) * 20 (W) * 14 (H) mm (with potentiometer)