ITEM NAME:DC-DC Digital Boost Step-up Voltage Converter LM2577 4-40V with Voltmeter hv2n Product Description Description: DC-DC Adjustable Digital Regulated Voltage Module LM2596s with Voltmeter calibration Bullet Points: 1.With voltmeter display, voltage meter error  ±0.1V, range 4~40V(Note: when the input voltage is lower than 4V, the onboard voltmeter does not work or display). 2.Large volume 5*5 touch key switches to measure the input and output voltage, and there is an indicator that can show which end of voltage you are measuring. For the initial boot, acquiescent digital tube display input voltage, and the input indicator IN will become brightened; Touch button slightly, then the digital tube displays output voltage, and the output indicator light OUT become brightened. And to maintain the final set, even if the power is switched on again. 3.The voltmeter can be turned off, press the switch for more than 1 seconds and less than 4 seconds, then loosen your grip it can be shut down. When the voltmeter is off, just press the switch shortly and turn on the voltmeter. 4.With the function of input and output voltage measurement error calibration . Press the switch for more than 4 seconds, after loosening your hands, it enters into input and output voltage measurement error calibration function, now the IN light on(Calibrate input end),digital tube display flickers to display correction value (original factory parameter is 0.0), at this time you can press the switch shortly to change this data(numerical range is -0.5~0.5, unit is V), a positive number indicates an upward adjustment, and a negative number indicates a downward calibration.After adjusting the calibration number of the input end, press the switch for more than 2 seconds, loosen your hands and then it is error calibration of output end, now the OUT light on(Calibrate output end),and display the calibration number of the output, the adjustment method is the same as input end. After finishing the calibra.And to maintain the final set, even if the power is switched on again. as input end. Output current: 3A(maximum). Output ripple:
