Patent · US Expired

Charging circuit for secondary battery

US7012405B2 · kind B2 · utility

48Cited by
23References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 12, 2002
Grant dateMar 14, 2006
Priority date
Expiry dateDec 31, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02J7/04
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A charging circuit for a secondary battery includes a constant-voltage circuit part outputting one of a plurality of predetermined constant voltages and charges the secondary battery by applying the constant voltage thereto, a detection circuit part detecting a battery voltage of the secondary battery, and a control circuit part controlling the selection of the constant-voltage in response to the detected battery voltage. Another charging circuit includes a constant-current circuit part outputting, to the secondary battery, one of two predetermined constant currents, a constant-voltage circuit part charging the secondary battery by applying a predetermined constant voltage thereto, a battery voltage detection circuit part detecting a battery voltage of the secondary battery, a charge current detection circuit part outputting a predetermined charge completion signal, and a charge control circuit part stopping operations of the constant-current circuit part and constant-voltage circuit part when receiving the charge completion signal.

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