At minimum, there are three connections required to use your regulator. Your battery’s positive cable should be connected to VIN. Your load should be powered by VOUT, and GND should be connected so that there is a common ground between all of your devices (battery, load, and regulator). The regulator will operate with the nSHDN pin and the PG pin disconnected. You can find more information about the pins in the “Connections” section of the product page description.