Abstract: A half-bridge inverter circuit is provided for converting a DC voltage source to an AC voltage waveform, and supplying the AC voltage waveform to a load. The half-bridge inverter includes an inverter comprising a first capacitor for supplying a positive output voltage and a second capacitor for supplying a negative output voltage during respective intervals of the output waveform. An equalizer, responsive to a control circuit, equalizes the voltage output from the first capacitor and the second capacitor in order to overcome non-symmetry of these voltages resulting from a non-symmetrical load.

Abstract: A memory device for recording information on a recording medium includes a recording mechanism for recording information on the recording medium. A control device controls the recording mechanism such that information is recorded in a first predetermined arrangement on a first portion of the recording medium and in a second predetermined arrangement on a second portion of the recording medium.

Abstract: An uninterruptible power supply is disclosed which is cheaper and more adaptable to various utility service inputs than presently available power supplies. A storage capacitor is placed between a boost AC/DC converter at the input and a DC/AC inverter at the output. A storage battery for maintaining constant voltage should the utility service power be interrupted is placed at the input, before the boost converter. Thus, a small battery is required because the boost converter is capable of boosting the battery's voltage to the voltage contained on the storage capacitor. A bidirectional semiconductor switch is provided in the boost converter to allow current to flow in both directions between its switch terminals when a AC input is applied. Appropriate control circuitry is provided which monitors the voltage at specific points throughout the circuit and controls operation of the bidirectional switch.