Features 1.With voltage meter display;voltage meter error of ±0.1V;the range among 0~40V. (note: to ensure the voltage meter accuracy, please make sure that the input voltage is 4.2V or more). 2.Voltage meter can be closed by long pressing button(minimum power loss). 3.The range of input voltage is 4.2~40V and output voltage is1.25V~37V ,which are continuously adjustable.(The input voltage must 1V higher than output voltage) 4.Maximum output current can be as high as 3A,but normal and stable working current is2A. 5.Use 150KHZ internal oscillation frequency,which is belong to the second generation of switch voltage regulator with low consumption and high efficiency. Where to use:1.experiment teaching 2.temporarily set up power supply in the outdoor 3.car(audio, electric fan)power supply What is special:LM2596 Step Down Power Module design based on XL2596 as main control chip,attached digital tube to display voltage at that time to highlight smart function. What’more, schottky diode provides protection of reverse connection. Testing Results Because the starting voltage is 4.2V, when testing you should set the input voltage 4.5V and the output voltage 1.4V. ICStation Team test it on the digital oscilloscope and the result shows that the actual testing of the product is in accordance with the description.