Abstract: Filter circuits having a resonator-based filter and a magnetically-coupled filter are disclosed. A filter circuit is deployed with a resonator-based passband filter connected to a magnetically-coupled filter which mitigates or reduces flyback of the resonator-based filter. The magnetically-coupled filter can be a passband filter with a relatively low insertion loss. The magnetically-coupled filter can be designed to mitigate flyback of the resonator-based filter by attenuating frequency response at selected frequency ranges.

Abstract: A high isolation duplexer/quasi circulator with two quadrature couplers is disclosed. Isolation between a transmit (TX) port and receive (RX) port of the quasi circulator is improved through use of two quadrature couplers. The quadrature couplers are coupled such that a first TX-RX signal path (from the TX port to the RX port) is shifted at or near 180 degrees from a second TX-RX signal path. These paths cancel each other to provide a high level of isolation between the TX port and the RX port. There are two signal paths between an antenna (ANT) port and the quadrature couplers for both TX signals and RX signals. A phase shift circuit is coupled to the ANT port of one or both duplexers such that the signals passing through the quadrature couplers to the ANT port are combined substantially in phase.

Abstract: A high isolation duplexer/quasi circulator with two quadrature couplers is disclosed. Isolation between a transmit (TX) port and receive (RX) port of the quasi circulator is improved through use of two quadrature couplers. The quadrature couplers are coupled such that a first TX-RX signal path (from the TX port to the RX port) is shifted at or near 180 degrees from a second TX-RX signal path. These paths cancel each other to provide a high level of isolation between the TX port and the RX port. There are two signal paths between an antenna (ANT) port and the quadrature couplers for both TX signals and RX signals. A phase shift circuit is coupled to the ANT port of one or both duplexers such that the signals passing through the quadrature couplers to the ANT port are combined substantially in phase.

Abstract: Filter circuits having a resonator-based filter and a magnetically-coupled filter are disclosed. A filter circuit is deployed with a resonator-based passband filter connected to a magnetically-coupled filter which mitigates or reduces flyback of the resonator-based filter. The magnetically-coupled filter can be a passband filter with a relatively low insertion loss. The magnetically-coupled filter can be designed to mitigate flyback of the resonator-based filter by attenuating frequency response at selected frequency ranges.

Abstract: The present disclosure relates to a high-power acoustic device with improved performance. The disclosed acoustic device includes a substrate, a die-attach material, and an acoustic die. The substrate includes a substrate body and a die pad on a top surface of the substrate body. The die-attach material is a sintered material and applied over the die pad. The acoustic die is coupled to the die pad via the die-attach material. Herein, the acoustic die includes a die body and a metallization structure, which is sandwiched between the die body and the die-attach material.

Abstract: The present disclosure relates to a high-power acoustic device with improved performance. The disclosed acoustic device includes a substrate, a die-attach material, and an acoustic die. The substrate includes a substrate body and a die pad on a top surface of the substrate body. The die-attach material is a sintered material and applied over the die pad. The acoustic die is coupled to the die pad via the die-attach material. Herein, the acoustic die includes a die body and a metallization structure, which is sandwiched between the die body and the die-attach material.