Abstract: A load control device for controlling the amount of power delivered to an electrical load from a source of AC power comprises a controllably conductive device and a variable gate drive circuit. The controllably conductive device is coupled in series electrical connection between the source and the electrical load to control the amount of power delivered to the load. The variable drive circuit is thermally coupled to the controllably conductive device and provides a continuously variable impedance in series with the control input of the controllably conductive device. The impedance of the variable drive circuit is operable to decrease as a temperature of the controllably conductive device increases and vice versa. Preferably, the variable drive circuit comprises an NTC thermistor. Accordingly, the switching times of the controllably conductive device, i.e.

Abstract: Apparatus and methods for regulating delivery of electrical energy to a lighting load are disclosed. An electrical waveform is received from a source of electrical energy. An integration value is generated based on a square of an amplitude of the received waveform. Electrical energy is delivered to the load until the integration value exceeds a threshold value. Thereafter, the delivery of electrical energy to the load is discontinued.

Abstract: A power control system for gas discharge lamps and other loads. According to a preferred embodiment, the system includes a main divertor in series or parallel with the load, and a variable divertor, which includes a controllably conductive device controlled by a control circuit, the variable divertor being selectively inserted in series with the load during each half cycle of the output voltage signal. The system obtains an improved load voltage waveform giving superior performance under reduced power output conditions. This system can be applied to a fluorescent lighting circuit having a plurality of conventional ballasts, achieving a dimming ratio of greater than 4 to 1, and can also be applied to other gas discharge lamp circuits, including high intensity discharge lamp circuits, to incandescent lamps, and to motors such as fan motors. It can further be applied to control the power supplied to solid-state switching units, including those having capacitive inputs.