title: A low-loss SAW-TV-IF filter with an extended impedance matching range.
abstract: A novel low-loss SAW (surface acoustic wave) filter for an intermediate frequency (IF) circuit in a color TV receiver has been developed. It consists of an apodized bidirectional and an unapodized group-type unidirectional transducer. The unidirectional transducer is designed to use different numbers of finger pairs in sending and reflecting electrodes for extension of the impedance-matching range. A thin-film capacitor for use as a phase shifter is monolithically fabricated on a 128 degrees Y-X LiNbO(3) substrate. A low insertion loss (11.3 dB) and impedance matching without adjustment are achieved at the same time without increasing the device chip size or number of electrical parts.
authors.affiliation: Hitachi Ltd., Yokohama.
authors.forename: J
authors.initials: J
authors.lastname: Yamada
authors.forename: Y
authors.initials: Y
authors.lastname: Fujita
authors.forename: T
authors.initials: T
authors.lastname: Shiba
authors.forename: T
authors.initials: T
authors.lastname: Toyama