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:
Jul. 03, 2007
Filed:
Apr. 04, 2005
Yasumasa Hasegawa, Kanegawa, JP;
Yasumasa Hasegawa, Kanegawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
An R-2R resistor circuit networkused in a filter circuit according to the present invention has a path through which each branch current flows to a next integrating capacitor and a path through which each branch current flows to a low impedance analog midpoint (ground potential) Vss. The path can be selected by digital control bit data Bn to Bfor each branch current. By this, a frequency characteristic of a filter using an integrator as a component may be changed with an accuracy of (½)(Gm)/Cf from (½)(Gm)/Cf to ((2−½)(Gm)Cf. As a result, by setting the setting bit width to 7 (n=6), a variable range of the frequency characteristic of over one hundredfold may be easily realized.