Abstract: A power supply circuit for discharge lamps having a load circuit with at least one discharge lamp and controlled switches with a switching control means which control the opening and closing of the switches to supply the load circuit with a high-frequency alternating signal. A recognition circuit, which recognizes the type of lamp connected to the load circuit by the power rating of the lamp, is provided. Control means which modify the switching conditions of the switches according to the type of lamp connected to the load circuit are also provided.

Abstract: A universal input dimming circuit for coupling an isolated external control signal into a variable output power supply, particularly those used for driving fluorescent lamps. Circuitry is incorporated which allows to discriminate between a DC control voltage or a relatively low-frequency pulsewidth-modulated signal using the same pair of input leads. By appropriate conditioning and waveshaping, the circuit produces a pulsewidth-modulated output which is then coupled across an isolation boundary and then demodulated to provide a command signal to the dimming ballast.

Abstract: An electronic ballast has a protection circuit particularly useful for smaller diameter gas discharge lamps including compact fluorescent lamps. The protection circuit prevents lamps from overheating by preventing the ballast from providing sustained output power when the magnitude of the ballast output voltage indicates abnormal lamp operation. The protection circuit has a voltage sensor which develops a voltage that is more negative than the negative DC supply terminal of the inverter so that an inexpensive low-voltage SCR can be used to turn off the inverter. The circuit provides automatic restarting of the ballast after a new lamp has been installed to eliminate the need for toggling the input power to the ballast.

Abstract: This inexpensive, small half connector includes at least one electrical terminal (usually a female contact). The half-connector body defines a hole to receive each terminal. Each terminal has at least one retaining element for engaging the half connector (e.g., a springy tang that snaps into behind an internal flange) to retain the terminal in the half connector. Each hole has a segment of relatively large transverse dimension to receive its terminal, generally with transverse clearance about the circumference of the terminal. Each hole also has a segment of reduced transverse dimension to receive the terminal and engage the retaining element(s) of that terminal to retain the terminal. Each hole has some integral feature--in other words, some structural element(s) integral with the half-connector body--for centering the terminal in the large-dimension segment of the hole.