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:
Dec. 07, 1999
Filed:
Jul. 17, 1998
Tadamasa Ushiroku, Ishikawa-ken, JP;
Abstract
A surface acoustic wave filter has a ladder type filter circuit including a plurality of series arm resonators and a plurality of parallel arm resonators. The electrostatic capacitance of at least one of the parallel arm resonators is larger than that of another of the parallel arm resonators, and the length of a bonding wire connecting the parallel arm resonator having the larger electrostatic capacitance to a ground potential of a package is greater than that of a bonding wire connecting the another of the parallel arm resonators not having the larger electrostatic capacitance to the ground potential, such that the values of additional inductances created by the bonding wires are different from each other. In this manner, attenuation poles are distributed so that the amount of attenuation in the stop band on the low-frequency side is greatly increased.