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:
Jan. 02, 2007
Filed:
Feb. 10, 2005
Seiichi Takahashi, Sagamihara, JP;
Takayoshi Nishiyama, Kyoto, JP;
Jun Nagai, Nagaokakyo, JP;
Eito Moromizato, Nagaokakyo, JP;
Seiichi Takahashi, Sagamihara, JP;
Takayoshi Nishiyama, Kyoto, JP;
Jun Nagai, Nagaokakyo, JP;
Eito Moromizato, Nagaokakyo, JP;
Murata Manufacturing Co., Ltd., Kyoto, JP;
Abstract
A switching power supply circuit reduces the time from start-up driving to normal operation while a soft-start is carried out with an output voltage Vout. A soft-start capacitor is charged during the start-up time. After a soft-start voltage Vz has reached a predetermined signal-output starting voltage Vlow, soft start of the output voltage Vout is carried out by controlling the operation based on the soft-start voltage Vz. A time constant for charging the soft-start capacitor is set as a time constant that causes the charge voltage of the soft-start capacitor to sharply increase at least until the soft-start voltage Vz reaches the signal-output starting voltage Vlow after the circuit has started driving, and is switched to a time constant that causes a rising trend of the charge voltage of the soft-start capacitor to become gentle with a predetermined time-constant switching timing. The start-up time is reduced by an amount equivalent to a reduction in the delay time from the start of driving to the start of voltage output.