I need help with a circuit that would switch to battery power when the AC power is disconnected. Does the following look like it would work? I am a little concerned that if the unit is running on AC power that there may be a “reverse” voltage across the transistors CE junction if the battery power is low. Will this damage the transistor or will the transistor just block the reverse current flow. Was also hoping to extend the battery life as long as possible. Is this design very low power or is there a better way.
5.7 KB Views: 293