Patent application number | Description | Published |
20120068788 | ELASTIC WAVE APPARATUS AND DUPLEXER - An elastic wave apparatus includes a balanced-unbalanced transforming function, and an elastic wave filter and a multilayer wiring board on which the elastic wave filter is mounted. The elastic wave filter includes an unbalanced terminal and first and second balanced terminals. External electrodes used are provided on the multilayer wiring board. A first internal line connects the first balanced terminal and the external electrode. A second internal line connects the second balanced terminal and the external electrode. The lengths or shapes of the first internal line and the second internal line are set so that a capacitance used for the improvement of a balance is generated in an adjacent area A where the first internal line and the second internal line are adjacent to each other. In the adjacent area A, the directions of currents passing through the first internal line and the second internal line are the same. | 03-22-2012 |
20120086520 | ELASTIC WAVE DEVICE AND DUPLEXER - An elastic wave device includes an unbalanced terminal and first and second balanced terminals. A longitudinally-coupled-resonator-type first elastic wave filter is provided between the unbalanced terminal and the first balanced terminal. An elastic wave filter, which is connected in parallel with the first elastic wave filter, is connected between the unbalanced terminal and the second balanced terminal. The current paths through which IDT electrodes of the elastic wave filter and the elastic wave filter are connected to ground terminals, are not symmetrical. | 04-12-2012 |
20120286896 | SURFACE ACOUSTIC WAVE FILTER DEVICE - A small-sized surface acoustic wave filter device having favorable filter characteristics includes a transmission-side surface acoustic wave filter chip including a ladder surface acoustic wave filter unit located on a piezoelectric substrate. The ladder surface acoustic wave filter unit includes a series arm connected between an input pad and an output pad and a plurality of resonators and including at least one first resonator connected to the input pad or the output pad. A die-attach surface is provided with an inductor connected to the first resonator. The inductor is arranged such that at least a portion thereof faces the first resonator and does not face any of the plurality of resonators and other than the first resonator. | 11-15-2012 |
20130154763 | ELASTIC WAVE BRANCHING FILTER - An elastic wave surface acoustic wave duplexer includes an antenna terminal, a transmission filter, a reception filter, and a plurality of elastic wave resonators connected in series between the antenna terminal and the reception filter. The reception filter is a longitudinally coupled resonator-type surface acoustic wave filter including a plurality of IDT electrodes and arranged along a propagation direction of elastic wave. A combined capacitance of the plurality of surface acoustic wave resonators is smaller than a capacitance of the IDT electrodes and included in the plurality of IDT electrodes and connected to the antenna terminal. | 06-20-2013 |
20130214873 | ELASTIC WAVE DEMULTIPLEXER - In an elastic wave demultiplexer having excellent isolation characteristics, a first ground wiring electrode is connected to a second ground wiring electrode, via first ground via-hole electrodes. The first ground wiring electrode is connected to ground land electrodes via second ground via-hole electrodes. The second ground wiring electrode is connected to a ground terminal via third ground via-hole electrodes. The number of the first ground via-hole electrodes is greater than the number of the second ground via-hole electrodes and the number of the third ground via-hole electrodes. | 08-22-2013 |
20140176257 | ELASTIC-WAVE FILTER DEVICE - An elastic-wave filter device includes a reception filter section including a longitudinally coupled resonator-type elastic-wave filter section that has a balanced-to-unbalanced conversion function and has improved common-mode isolation characteristics. Among IDT electrodes of a filter section, each of the other comb-shaped electrode of a first IDT electrode including a pair of comb-shaped electrodes, one of which is connected to a first balanced-signal terminal, and the other comb-shaped electrode of a second IDT electrode including a pair of comb-shaped electrodes, one of which is connected to a second balanced-signal terminal, is connected to one of ground electrodes that are provided on a piezoelectric substrate. Inductors are provided on the piezoelectric substrate, and each inductor is connected between the other comb-shaped electrode of one of the first and second IDT electrodes and one of the ground electrodes. | 06-26-2014 |
20140368295 | SIGNAL SEPARATION APPARATUS - A signal separation apparatus includes a piezoelectric substrate on which a transmission filter and a reception filter are provided. The reception filter includes first, second and third longitudinally coupled resonator-type elastic wave filter devices and the first, second and third longitudinally coupled resonator-type elastic wave filter devices each including a two-stage cascade connection structure. The signal separation apparatus further includes virtual ground wiring lines that are not connected to a ground potential and that connect ground terminals of adjacent longitudinally coupled resonator-type elastic wave filter units to each other on at least one of a first, second, and third group-A longitudinally coupled resonator-type elastic wave filter units side and a first, second, and third group-B longitudinally coupled resonator-type elastic wave filter units side. | 12-18-2014 |