I love this module so much! It is the upgraded version of the Adjustable Mini DC-DC Module. It integrated a voltage meter with the DC-DC module – LM2596S, with this function, you can monitor your project much more easily. The voltage meter can measure the input voltage or output voltage, which is adjustable by the potentiometer, with a precision of ±0.1V. Note that the voltage meter would not work if the input voltage is below 4V. Press the button to switch voltage to measure, the input voltage and output voltage. There are also 2 LEDs (IN and OUT) to indicate which voltage is measured by the voltage meter. You can also close the voltage meter by long pressing the button (1S< press time < 4S), after you release the button, the voltage meter will be close.
Specification
Input Voltage: 4V~40V (1.5V higher than the output at least)