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:
Jul. 12, 2011
Filed:
Aug. 15, 2008
Ahmad Bahai, Lafayette, CA (US);
Ali Djabbari, Saratoga, CA (US);
Qingguo Liu, Sunnyvale, CA (US);
Jianhui Zhang, San Jose, CA (US);
Ahmad Bahai, Lafayette, CA (US);
Ali Djabbari, Saratoga, CA (US);
Qingguo Liu, Sunnyvale, CA (US);
Jianhui Zhang, San Jose, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
Voltage conversion and charging circuitry and method for converting an alternating current (AC) voltage to a direct current (DC) voltage for charging an energy storage element (e.g., battery or supercapacitor). An output capacitance, which is initially charged quickly for use in the slower charging of a battery, also maintains the charge on an input capacitance which provides power for the charging control circuitry during such charging process. In accordance with a preferred embodiment, the DC charging current is substantially constant during a first time interval following which the DC charging power is substantially constant during a second time interval.