I have several batteries in series and the ground point is in the center, such that I can achieve a negative and positive voltage. The OP amp uses both negative and positive voltage. Let's assume I am using two 9v batteries.
If I were to place a SPST on ground, is this sufficient? My confusion/worry is if I have the switch open, then it essentially is creating a 18V source:
With the switch open, the chip will have no source to the battery center tap. This seems safe but the chip would still be connected to both ends of the in-series 18V source (since it required the positive and negative 9v.)
Could the circuit somehow be closed inside of my op amp and pump double the voltage through my chip? Should I be using a DPST like this instead: