Patent · US Expired

Computer system which is operative to change from a normal operating state to a suspend state when a power supply thereof detects that an external source is no longer providing power to said power supply at a predetermined level

US5748972A · kind A · utility

21Cited by
15References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 29, 1996
Grant dateMay 5, 1998
Priority date
Expiry dateApr 29, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F1/30
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Described is a personal computer system which includes a central processing unit (CPU) and power management circuitry (PMC) in circuit communication with the CPU. A switch is coupled to the PMC. A power supply is coupled to the CPU, PMC and the switch and includes circuitry for selectively providing system power to the computer system and auxiliary power to the PMC (1) from an external source or (2) from an internal source. When the system is in a normal operating state and the external source stops providing power at a predetermined level (e.g., blackout or brownout) to the power supply, the power supply is operative to change to its internal power and generate a control signal to the switch. The control signal causes the switch to activate a closure event and generate another control signal. In response to the activation of the latter control signal, the power management circuitry is operative to cause the system to change to the suspend state wherein the entire state of the system is safely saved to a non-volatile storage device.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.