Patent ID: 7924118
Filing Date: 2011-04-12
Classification: H03H

Abstract:
1. A duplexer comprising: a transmission elastic wave filter; a reception elastic wave filter; and a laminated substrate on which the transmission elastic wave filter and the reception elastic wave filter are provided; wherein the transmission elastic wave filter includes a first piezoelectric substrate, a first filter unit provided on the first piezoelectric substrate, and a transmission output pad provided on a bottom surface of the first piezoelectric substrate and connected to the first filter unit; the reception elastic wave filter includes a second piezoelectric substrate, a second filter unit provided on the second piezoelectric substrate, an unbalanced pad, and first and second balanced pads, the unbalanced pad and the first and second balanced pads being provided on a bottom surface of the second piezoelectric substrate and connected to the second filter unit; the second filter unit comprises: the laminated substrate comprises: a distance between the second ground pad and the coil is greater than a distance between the first ground pad and the coil, and the second inductance component is less than the first inductance component.