| 摘要 |
<p>There is provided a SAW duplexer in which a bridging inductor can be formed without increasing the area of a package substrate, which has a good filter characteristic, and which can achieve size reduction. A SAW duplexer (1) includes a first SAW filter having a passband with a relatively low frequency, and a second SAW filter having a passband with a relatively high frequency. The first and second SAW filters each have a ladder-shaped circuit configuration. A bridging inductor is connected in parallel to at least one serial arm resonator in the second SAW filter. The bridging inductor includes a coiled portion provided on a multilayer package substrate. The coiled portion is formed by connecting first to third wires (23, 26, and 29) provided on first to third layers by via-hole conductors. First, third, and fifth via-hole conductors (24, 27, and 30) that form a coil return wire portion are disposed inside the coiled portion.</p> |
