Patent · US Expired

System and method for detection of zero current condition

US6507175B2 · kind B2 · utility

10Cited by
8References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 15, 2001
Grant dateJan 14, 2003
Priority date
Expiry dateOct 15, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B70/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The present invention is directed to a circuit that is configured to detect a zero current condition at a certain point. The circuit includes a current mirror coupled to two transistors, where the first transistor is coupled to ground and the second transistor is coupled to the point being sensed. The outputs of both the first transistor and the second transistor are each coupled to an input of a comparator. The comparator is configured to determine when an equal voltage condition is present at the two inputs, which signifies a zero-current condition. Such a zero current detector can be used in a buck regulator to prevent a current flow from load to ground and attendant inefficiencies that result. An alternative embodiment involves the use of a controller to sense three different voltages to determine the state of the switches.

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