The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 05, 1981
Filed:
Dec. 27, 1978
Howard Handler, Westminster, CA (US);
Datapower, Inc., Santa Ana, CA (US);
Abstract
A gas discharge lamp is connected across an inductor and in series with a solid state switching device and a resistor, and this combination is connected across a rectified AC voltage source. This switching device is controlled by a monostabile multivibrator, the input of which is connected to the output of a comparator amplifier sensing the difference between the voltage drop across the above-mentioned resistor and a voltage which may be selected to vary light intensity. The secondary winding of a step-up transformer connected to a capacitive discharge device is placed in series with the lamp. Control circuitry is provided to apply a large ignition voltage to the lamp while preventing damage to the switching device by simultaneously holding it in its conductive state. A diode rectifier provides an alternate current path across the secondary winding to prevent the inductance of the secondary winding from affecting normal lamp operation. Means are provided to cancel the contribution of lamp current to the voltage drop across the resistor sensed by the comparator, thereby rendering power consumed by the circuit independent of the effective resistance of the lamp.