AC-DC wall adapters aka "wall warts" are power supplies that convert 120Vac (or 220Vac) to a lower DC voltage. Most electronic devices in homes and businesses are powered by this type of power supply. They may or may not be regulated. If unregulated the output voltage can fluctuate depending on the load. The output load is always higher than listed because it drops to the correct voltage when in use, so it is a good idea to get an AC-DC wall adapter that operates close to the desired current. If you use a regulated power supply it will maintain the correct voltage as long as the maximum load is not exceeded. We have a large selection of regulated and unregulated DC-DC wall adapters. Note: If we refer to a device as an AC-DC transformer it is not regulated. If we call it a power supply it is regulated.
