- Joined May 28, 2009
I am more an RF guy than a power supply guy, so I will need some help with this one. I can use a standard computer power supply for the main power supply 115-240 VAC in/12 VDC out @ 1 amp. I need to incorporate a circuit that can charge a 12V battery and switch over to it if the main power fails, then back to main power when the main power turns back on. The device I am running draws 150mA, and runs on 12VDC. Is it practical to base the circuit on using a JFET as a switch, so when the gate voltage goes to zero, it will conduct?