12 volt 20 amp smps A 12V 20A SMPS (Switched Mode Power Supply) is a power supply device that converts AC (alternating current) power from a wall outlet into DC (direct current) power with a voltage output of 12 volts and a current rating of up to 20 amps. This type of power supply is commonly used in various electronics applications such as LED lighting, audio systems, and other devices that require a high level of electrical current.