Let’s say you just got a new awesome electronic module that requires 5 volts in order to work but all you have is a 12-volt power source. The easiest solution would be to use an LM7805 voltage regulator with an input and output capacitor to step down 12 volts to 5 volts but if we measure the input and output power, we can see that the efficiency is quite low and gets even worse with higher input voltages because the regulator is basically a variable resistor that converts the excess power into heat which is not recommended when the power source is a battery.
Buck Converter Step Down Module LED digital voltmeter tube, the accuracy is adjustable function, can be aimed at your multimeter adjustable accurate.
Press the right key to let the display show the input or output voltage. when the right “OUT” led light, it shows output, the left “IN” led show input.
How to adjust the accuracy?
Output voltage (Input voltage)calibration steps
Step 1, Adjust the right button so that “OUT” (“IN”)LED lighted, the voltmeter shows the value of output voltage; Press the right button for more than 2 seconds, release, voltmeter and “OUT” ( “IN”)LED flashes in synchronization so that you enter the output voltage calibration mode.
Step 2, Press the right button (normal speed), the voltage value is adding up a unit; Press the left button, minus a unit; Due to a unit is less than 0.1V, the minimum voltage display to 0.1V, so you need to continuously press 1-5 times to see the voltmeter change 0.1V, how many times voltmeter change 0.1V by pressing the key, depending on the current display voltage, the higher the voltage, the fewer the number of press.
Step 3, press the right button for more than 2 seconds, release, to exit the output voltage calibration mode. All parameters set to automatically power down to save.
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LM2596 DC Buck Converter Module