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:
Dec. 11, 2018

Filed:

Mar. 24, 2017
Applicant:

Alps Electric Co., Ltd., Ota-ku, Tokyo, JP;

Inventors:

Tatsumi Fujiyoshi, Miyagi-ken, JP;

Yasuhiko Hiratate, Miyagi-ken, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G06F 3/044 (2006.01); H03K 17/955 (2006.01); G06F 3/041 (2006.01); H03K 17/945 (2006.01);
U.S. Cl.
CPC ...
G06F 3/044 (2013.01); G06F 3/0416 (2013.01); H03K 17/955 (2013.01); G06F 2203/04101 (2013.01); G06F 2203/04107 (2013.01); H03K 2017/9455 (2013.01); H03K 2217/960705 (2013.01);
Abstract

In a case where the amplitude of a detection voltage is increased, the amplitude of a drive current flowing in a detection-target capacitor also increases, and thus, the amplitude of a detection current also increases. In this case, the increase in amplitude of the detection current is not directly restricted by the condition of a power supply voltage range enabling a circuit to operate. For this reason, a current conversion ratio of a current output circuit or a capacitance value of a capacitor of a current-voltage conversion circuit is set to an appropriate value so as not to cause a voltage to exceed the power supply voltage range, thereby preventing the amplitude of the detection current from being restricted by the condition of the power supply voltage range. Therefore, it is possible to increase the amplitude of the detection voltage to a maximum within the power supply voltage range.


Find Patent Forward Citations

Loading…