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:
Aug. 25, 1992
Filed:
Aug. 31, 1990
David J Allard, Boynton Beach, FL (US);
Salvatore R Riggio, Jr, Boca Raton, FL (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
The present off/on delay circuit operates within the power supply of a microcomputer system to interrupt transfer of regulated DC voltage to the system microcomputer and attachments in respect to indications of power disturbance and system switch status produced in the supply. Upon termination of such indications, this circuit selectively delays reappearance of regulated DC voltage to the level required for system operation so that whenever the microcomputer resets, the attachments must also reset; thereby preventing lockout impasses in the system rebooting process. The circuit operates in response to a plurality of DC voltage indications in the power supply, including at least an indication distinguishing the state of AC source power as either good or bad, and an indication distinguishing the state of a manually operable system power switch as either on or off. In one embodiment, the delay in reappearance of regulated DC operating voltage is chosen to be either relatively fast or slow depending upon how long the system operating voltage has been deactivated. Thus, the slow delay is chosen so as to effectively lengthen the effects of short duration outages or disturbances sufficiently to preclude lockout.