Surface acoustic wave apparatus

• Main Authors: KAWACHI OSAMU, TAJIMA MOTOYUKI, ABE TAKUYA
• Format: Patent
• Language: Chinese; English
• Published: 03.09.2008
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS

Improvement on an insertion loss, as well as phase balance, is obtained in surface acoustic wave device. In the surface acoustic wave device, when an aperture length of the electrode fingers of an interdigital transducer for input or an interdigital transducer for output is defined as X, the interdigital transducer for input or the interdigital transducer for output includes two split interdigital transducers respectively including electrode fingers having an aperture length of approximately X/2, and electrodes of respective electrode fingers in the first and second split interdigital transducers are extracted from the two split interdigital transducers, and disposed in such a way as signals in the two outputs or inputs connected to a balanced terminal pair have a phase difference of 180 DEG , and the two split interdigital transducers are connected in series by a common electrode of solid shape, of which electrode width is greater than twice the pitch of the electrode fingers in the two split interdigital tr