Patent ID: 9124238
Filing Date: 2015-09-01
Classification: H03H

Abstract:
1. A duplexer, comprising: a transmitting filter connected between an antenna terminal and a transmitting terminal; a receiving filter disposed between the antenna terminal and a receiving terminal, the receiving filter including a double-mode filter having an input ground and an output ground; a package substrate that has a first substrate, a die attach layer that is patterned onto the first substrate, a second substrate that faces the first substrate, and an inner layer located between the first substrate and the second substrate, the die attach layer being on a first side of the first substrate opposite to a second side facing the second substrate, the receiving filter being mounted on the die attach layer on the first substrate, the receiving filter being thereby provided over the first substrate on the first side opposite to the second side of the first substrate facing the second substrate; a common ground terminal in the die attach layer, said common ground terminal being in contact with the input ground and the output ground of the double-mode filter so that the input ground and the output ground are commonly grounded; an input-side ground terminal of the input ground of the double-mode filter, the input-side ground terminal constituting a portion of the inner layer; and an output-side ground terminal of the output ground of the double-mode filter, the output-side ground terminal being formed separately from the input-side ground terminal and constituting a portion of the inner layer.