Function and role of the module: 1 low input voltage high output voltage . Achieve boost function. 2 The output voltage is adjustable. 3 ultra-small size using 7805 as a three-terminal regulator IC pin TO220 package. Input voltage range :3.6-30V. The output voltage range the output voltage 3.8V to 36V. Output Voltage Regulator Features: Load regulation is less than 5%. Output Current : IC internal switch of this module is 1.5A but for security and heat considerations recommended load power consumption of the module is less than 0.8W which is the output of 5V load in less than 160MA. Note : The higher the negative output load capacity will be relatively decreased . Conversion efficiency of about 78% depending on the pressure a little bit of input and output less output voltage ripple 80MV. Usage: When used note : Be sure to pick an input and output pin is greater than 100UF electrolytic capacitor to ground. Input and output filter capacitor is connected to the positive input pin negative ground capacitor voltage must be greater than the input and output voltages. Also: if you want to use a battery boost ordinary cell phone batteries and 18650 can be directly boost while nominal 1.2V or 1.5V battery # 5 or # 7 below 3V batteries etc. to three strung together to boost .