Patent ID: 8836224

Claim:
A converter plug for an LED light string that plugs into a household alternating current socket that converts alternating current household power to a low voltage direct current output comprising: an enclosure that is watertight and has a shape and size similar to a wall plug; plug blades that are molded into said enclosure having a watertight seal with said plug blades; a printed circuit board having converter circuitry mounted on at least one surface of said printed circuit board, said printed circuit board securely mounted in said enclosure, said converter circuitry comprising; a full wave rectifier that rectifies a source of alternating current from a household socket to produce a rectified alternating current signal at an output of said rectifier; a low pass filter, connected to said output of said rectifier, that filters said rectified alternating current signal to provide a substantially direct current signal; a filter absorber that protects said converter circuit from voltage spikes; a high speed switching transistor that modulates said direct current signal to produce a modulated direct current signal having a modulation frequency; a first coil, in a transformer, coupled to said modulated direct current signal that induces voltage changes in a second transformer coil to produce a second induced voltage and induces voltage changes in a third transformer coil to produce a third induced voltage; a high speed directional filter connected to said second transformer coil that produces said direct current output from said second induced voltage; a voltage detection circuit connected to said third transformer coil that produces a monitoring signal, without an optical coupler, from said third induced voltage on said third transformer coil that is proportional to said second induced voltage on said second transformer coil; a controller that controls said modulation frequency of said modulated direct current signal in response to said monitoring signal.