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:
Apr. 24, 2012
Filed:
Apr. 13, 2009
Yong IL Kwon, Gyunggi-Do, KR;
Kyung Hee Hong, Seoul, KR;
Sang Hoon Hwang, Seoul, KR;
Tah Joon Park, Gyunggi-Do, KR;
Yong Il Kwon, Gyunggi-Do, KR;
Kyung Hee Hong, Seoul, KR;
Sang Hoon Hwang, Seoul, KR;
Tah Joon Park, Gyunggi-Do, KR;
Samsung Electro-Mechanics Co., Ltd., Gyunggi-do, KR;
Abstract
In a key scanning circuit, a key input unit has a parallel connection of a plurality of circuits having a series connection of resistors and switches between a power supply input terminal and a key scanning terminal. The resistors connected in parallel have different resistances. A current mirror has a first terminal connected to the key scanning terminal. A reference current source is connected between a second terminal of the current mirror and the power supply input terminal.