Description:

• The DC-DC adjustable step-down power supply Buck Module LM2596 voltage regulator with voltmeter comes with a digital display.
• Features/Operating Instructions:
• With a voltmeter display, voltmeter error rate is ± 0.1V, range is 4 ～ 40V. (Note: if the input voltage is lower than 4V, the onboard voltmeter does not work and does not display).
• Use the button to switch between measuring input or output voltage.
• An indicator light shows which terminal voltage is being measured.
• By default, the input voltage is displayed and the input indicator IN is on.
• When the button is pressed, the digital tube displays the output voltage, and the output indicator OUT is on.
• The last setting is stored, even after switching off.
• The voltmeter can be turned off.
• Press and hold the switch for more than 1 second and less than 4 seconds.
• After the voltmeter is turned off, just press the switch briefly to turn on the voltmeter.
• The input and output voltage measurement error calibration function - long press the switch for more than 4 seconds to enter the voltage measurement error calibration function.
• Currently, the IN light is on (calibrating the input terminal), and the digital display flashes to display a positive value (factory parameter is 0.0).
• At this time, you can change this value by pressing the button shortly (the value range is -0.5 ～ 0.5, the unit is V).
• A positive number indicates upward calibration, and a negative number indicates downward calibration.
• After adjusting the calibration value of the input terminal, press and hold the button for more than 2 seconds, and enter the error calibration of the output terminal after releasing.
• Currently, the OUT light is on (calibrating the output terminal), and the calibration value of the output terminal is displayed.
• The adjustment method is the same as that of the input terminal.
• After the calibration value at the output ends, press and hold the button for more than 2 seconds, and save the set value and return to the normal display voltage after letting go.
• The set correction value will take effect immediately and will not be lost after power failure. (With this function, you can meet your higher accuracy requirements)
• The input voltage must be more than 1v higher than the voltage to be output.
• The maximum output current can be as high as 3A if a heat dissipation device is used.
• It is recommended that the working current be about 2A.
• Some customers reported that the output voltage of the module cannot be adjusted and is always equal to the input voltage.
• When you encounter this kind of problem, please turn the potentiometer counterclockwise for more than 10 turns, and then use the module to adjust the voltage normally.
• Because when the step-down module leaves the factory, the default output voltage is about 20V.

Specification:

• Input Voltage: DC 4~40V.
• Voltmeter error rate is ± 0.1V.
• Output Voltage: DC 1.25~37V.
• Output Current: 2A (for stable operation), 3A max.
• Voltmeter: 0~40V.
• Voltmeter Accuracy: .+/-0.1V.
• The unit adopts the internal oscillation frequency of 150KHz.
• Dimensions: 66 x 36 x 12mm.