Features:
- DC-DC step-down module
- Thickened circuit boards
- Advanced solid-state capacitor
- Short circuit and over-temperature protection
- 100% tested, sealed in anti-static packaging

Kindly Note:
1. Input voltage must be 1.5 V higher than the output voltage, no boost
2. Do not reverse the input and output interface
3. Keep output under 2A (or 15W), and use a heat sink when for a long time working

How to Calibrate the Digital Tube Voltmeter
(Optional steps for the person who need a highly accurate voltage value)
1. Short press the left "ON/OFF" button to start up the digital tube voltmeter. Long press(>1s, 2. Long press(>4 seconds) the left button to enter self-calibration of voltage measurement(calibration range: -0.5-0.5V, factory setting is 0.0).
"IN" indicator lights = input voltage measurement calibration starts.
Then, long press(>2 seconds) the right "Mode" button, "OUT" indicator lights = output voltage measurement calibration starts.
Tap the left / right button to reduce / rise by one unit (since the voltage value of one unit is less than 0.1V, you need to 1-5 times tap the button continuously, so that the voltmeter can change by 0.1V)
3. After calibration, long press(>2 seconds) the right "Mode" button to preserve the adjusted value(no loss with outage) and back to normal voltage display.

Specifications:
- Model: LM2596 / Digital Tube Voltmeter
- Input voltage: DC 4V - 40V
- Output Voltage: DC 1.5V - 35V (adjustable)
- Output Current: 3A (max.)
- Conversion Efficiency: 92% (max.)
- Switching Frequency : 150KHz
- Operating Temperature: -45℃ to +85℃
- Size(L x W x H): 57*36*13mm
- Weight: 21g

Package List:
3x DC-DC Buck Converter Module with LED Display