'''VBAT''' is an input pin - it is connected to the GPS real time clock battery backup. We suggest using the battery spot on the back but if you have a project with a coin cell or other kind of battery that you want to use (and its under 3.3V) you can connect it to the VBAT pin. If you do this, be sure to cut the trace on the back between the RTC solder pads | '''VBAT''' is an input pin - it is connected to the GPS real time clock battery backup. We suggest using the battery spot on the back but if you have a project with a coin cell or other kind of battery that you want to use (and its under 3.3V) you can connect it to the VBAT pin. If you do this, be sure to cut the trace on the back between the RTC solder pads |