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:
Feb. 27, 2001
Filed:
Jan. 28, 1997
Robert L. Jardine, Cupertino, CA (US);
Larry D. Reeves, Palo Alto, CA (US);
Murali Basavaiah, Sunnyvale, CA (US);
Garry Easop, Sunnyvale, CA (US);
Tandem Computers Incorporated, Cupertino, CA (US);
Abstract
An apparatus and method for tolerating failure of the AC power source in a power supply switchable between the AC power source and a battery, in a processor system having a set of one or more components subject to being powered down. When the failure of the AC power source is recognized, the power supply is switched from the AC power source to the battery. For a first period of time, the battery powers the processor system with all components powered on. The battery then powers the processor system with the specific set of components powered off for a second period of time. In one embodiment, a determination is made that the battery can power the processor system with the set of components powered down for a predetermined period of time. A determination of the first period of time is then made as the capacity of the battery exceeding the predetermined period of time, if the excess capacity is used to power the processor system with the set of components powered on. In effect, a processor system incorporating one embodiment of the invention rides through a first period of a power outage, operating as normal and masking the loss of AC power. For a second, predetermined period, the processor system shuts down optional hardware and maintains the state of memory using the battery power.