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, 1998
Filed:
Oct. 03, 1996
Bruce Allen Heaston, West Milton, OH (US);
Robert John Disser, Dayton, OH (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A power latch circuit for a computer is improved by the expansion of an activate control circuit to include overvoltage protection circuitry. The activate control circuit is responsive to either an activate input circuit or a feedback latch circuit to activate an activating transistor which in turn activates a series transistor providing power from a DC electric power source through a voltage regulating circuit to the computer, which is programmed to turn itself off by activating a deactivate transistor to deactivate the activating and series transistors. In the improved circuit, the activate control circuit includes elements for activating the activating transistor and series transistor in a switching mode when the output voltage of the series transistor does not exceed a fixed limit voltage and in a voltage regulating mode when the output voltage of the series transistor exceeds the fixed limit voltage, whereby an increase in the output voltage of the series transistor beyond the fixed limit voltage is reduced. The activate control circuit further deactivates a hold-off transistor during activation of the activating and series transistors, regardless of the mode of operation.