An uninterruptible power supply circuit is provided. The uninterruptible power supply circuit includes a first diode, a second diode, a bridge rectifier, and one or more electrical loads. The first diode, the second diode, the bridge rectifier, and the one or more electrical loads are electrically connected in the uninterruptible power supply circuit to drive the one or more electrical loads with a DC voltage or the intended AC supply voltage when the AC supply voltage is cutoff.