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:
Dec. 01, 1987
Filed:
Apr. 03, 1986
John Tardy, Somerville, NJ (US);
American Telephone and Telegraph Company AT&T Technologies, Inc., Berkeley Heights, NJ (US);
Abstract
An off-line regulating power supply utilizes a regulating transistor which perates in a dissipative mode for only a portion of each half cycle of an input AC voltage in order to regulate an output voltage by truncating the input AC sinewave. This AC input signal is full wave rectified and coupled to a primary winding of a power transformer through the regulating transistor. One of a plurality of secondary windings is coupled to a voltage threshold detector which responds instantaneously to attainment of the threshold in each half cycle of operation to bias the regulating transistor from a saturated condition to an active dissipative impedance state which limits the output voltage to the threshold level. As the input AC sinewave peaks and declines in value, the regulating transistor is again biased into saturation when the voltage applied to the threshold detector drops below the threshold level.