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.

Date of Patent:
May. 01, 2018

Filed:

Aug. 31, 2015
Applicant:

Azbil Corporation, Tokyo, JP;

Inventor:

Tetsuya Kajita, Tokyo, JP;

Assignee:

Azbil Corporation, Tokyo, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02M 1/36 (2007.01); H03K 17/22 (2006.01); G05F 3/26 (2006.01); G05F 3/30 (2006.01); H02M 3/04 (2006.01);
U.S. Cl.
CPC ...
H03K 17/22 (2013.01); G05F 3/26 (2013.01); G05F 3/30 (2013.01); H02M 1/36 (2013.01); H02M 3/04 (2013.01);
Abstract

Disclosed is a startup circuit comprises a current path comprising a circuit including a P-channel MOS transistor, a P-channel MOS transistor, and an N-channel MOS transistor connected in series. After a constant current circuit is started, the N-channel MOS transistor is turned on, an operating current is fed through the current path, and an N-channel MOS transistor is turned off to cut off a startup current. After the startup current is cut off, the gate voltage of the P-channel MOS transistor is controlled by the voltage (bias voltage during operation of the constant current circuit) of a node, a drain-source voltage of the P-channel MOS transistor is reduced, and the operating current flowing through the current path is limited.


Find Patent Forward Citations

Loading…