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:
May. 18, 2010
Filed:
Jun. 11, 2004
Hiroshi Usui, Saitama, JP;
Hiroshi Usui, Saitama, JP;
Sanken Electric Co., Ltd., , JP;
Abstract
When an AC power supply () is powered up, a constant current supply section () supplies a constant current to a capacitor (C) to charge the capacitor (C). When a voltage across the capacitor (C) becomes equal to or greater than a predetermined voltage, a switch control section () sets a switch () off. When an output current drops to lead to a light load, a load detecting circuit () stops the operation of a PWM control circuit () and activates a timer (). The timer () supplies a switch-ON signal to the switch control section () when it is activated and a predetermined time measured elapses. When supplied with the switch-ON signal, the switch control section () sets the switch () on. When the switch () is set on, the capacitor (C) is charged again, applying a voltage to the PWM control circuit ().