Welcome to our shop! Item Type: 18650 Lithium Battery Step Up Module Input Voltage: 5V Output Voltage: 4.7V - Please note that when used as a UPS, the SW pin should be shorted to ensure real-time output. This allows the module to start battery power supply immediately when the power is off. - If you use the module as a mobile power supply, you can add a switch to the SW pin. When the switch is off, there will be no static loss, making it very power-saving. - If you choose not to add a switch to the SW pin, you can still short it. After completing all the tests, you can solder down the output indicator. This can reduce current consumption without affecting the circuit's normal output. - During operation, various reasons such as accidental touch or wrong connections may cause the module to enter a protection state and stop outputting. In such cases, you can connect the board charging port to a 5V charger to activate the board and restore output after power-on. - Please be aware that MOS components on the circuit board are susceptible to static electricity damage. Therefore, it is recommended to use a soldering iron with a grounding wire and take anti-static measures. 100% Satisfaction: Our customers are our top priority. If you find any product problems after receiving the goods, such as damage and incorrect quantity of goods, please contact the seller immediately. We try our best to provide you with satisfactory after-sales service.