Product DescriptionDC-DC Buck Step Down Module LM2596 DC/DC 4.0~40V to 1.25-37V Adjustable Voltage Regulator With LED VoltmeterFeatures1. Input voltage range:4-40VDC2. Output voltage range:1.25-37VDC adjustable3. Output current: 3A(MAX), The maximum output current can be up to 3A, it is recommended to use within 2.0A, more than 2A plus heat sink4. voltmeter range: 0 to 40V, error ±0.1V5. Input reverse polarity protection6. Built in output short protection function7. Built in thermal shutdown function8. L x W x H =6.7*3.4*12 cm9.Weight: 22g10.LEDdigital voltmeter tube, the accuracy is adjustable function, can be aimed at your multimeteradjustable accurate.11.Press the rightkey 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?(1)Output voltage calibration stepsStep 1, adjust the right button so that “OUT” LED lighted, the voltmeter shows the value of output voltage; Press the right button for more than 2 seconds, release, voltmeter and “OUT” LED flashes in synchronization so that youenter 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.(2)Input voltage calibration stepsStep 1, adjust the right button so that “IN” LED lighted, the voltmeter shows the value of input voltage; press the right button for more than 2 seconds, release, voltmeter and “IN” LED flashes in synchronization so that you enter the input voltage calibration mode.Steps 2 and 3, consistent with the output voltage calibration method.Note Some customers report: “The module can not be adjusted, the output voltage is always equal to the input voltage.” When you encounter this problem, please counterclockwise rotation of the potentiometer 10 laps or more, then you can adjust the output voltage. Because the factory default output voltage is 20V.
LM2596S DC-DC Adjustable Step-Down Module (3A) With LED Voltmeter Module