An ultrasonic device may include an electromechanical ultrasonic system defined by a predetermined resonant frequency, in which the system may include an ultrasonic transducer coupled to an ultrasonic blade. A method of estimating a state of an end effector of the ultrasonic device may include applying a drive signal defined by a magnitude and a frequency to the ultrasonic transducer, sweeping the frequency of the drive signal from below a first resonance to above the first resonance of the electromagnetic ultrasonic system, measuring and recording, impedance/admittance circle variables R.sub.e, G.sub.e, X.sub.e, and B.sub.e, comparing, the measured impedance/admittance circle variables R.sub.e, G.sub.e, X.sub.e, and B.sub.e to reference impedance/admittance circle variables R.sub.ref, G.sub.ref, X.sub.ref, and B.sub.ref, and determining, a state or condition of the end effector based on the result of the comparison. An electromechanical ultrasonic system may include a control circuit to effect the method.

An ultrasonic device may include an electromechanical system defined by a resonant frequency and further include an ultrasonic transducer coupled to an ultrasonic blade. The device may be composed of two or more components, one of which is reusable and one of which is disposable. A method of detecting a proper installation of the components may include determining a spectroscopy signature of the blade coupled to the transducer, comparing the signature to a reference signature, determining an installation state of the components based on the comparison, and controlling a delivery of power to the transducer based on the comparison. The method may include enabling an operation of the device when the installation state of components is proper. The method may further include disabling the device when the installation state is not proper and generating a warning. The warning may be visible, audible, or tactile.

An acoustic matching material for gas measurement including a matrix material having an acoustic impedance and an acoustic impedance reduction material, having an acoustic impedance lower than the acoustic impedance of the matrix material, the acoustic impedance reduction material being dispersed in the matrix material to create an acoustic impedance graduation through a thickness of the matching material.

A filter device includes a first filter including series resonators and parallel resonators, a first inductor connected in parallel between a first terminal and the first filter, a second inductor provided in series between the first filter and a second terminal, and a third inductor provided in series in a channel connecting the parallel resonator and ground, the third inductor is incorporated in a multilayer substrate, the first filter is mounted on a main surface of the multilayer substrate and incorporated in a filter chip, and the first inductor and the second inductor are chip inductors including coil conductors and are mounted on the main surface of the multilayer substrate beside the filter chip so as to be adjacent to each other and such that coil axes thereof are orthogonal or substantially orthogonal to each other.

An acoustic impedance matching device can facilitate acoustic transmission across an interface formed by materials having a very large acoustic impedance mismatch (e.g. air-water, or air-elastic polymer). The device can include a first medium. The first medium can have a first acoustic impedance. The device can include a second medium. The second medium can have a second acoustic impedance. The second acoustic impedance can be substantially greater than the first acoustic impedance. Thus, the first acoustic impedance and the second acoustic impedance are substantially mismatched. An interface can be defined between the first medium and the second medium. A bubble can be located in the second medium or the interface. The bubble can act as a resonator and can enable efficient sound transmission despite the large impedance mismatch of the first medium and the second medium.

A power supply circuit includes a switchable match, including a high voltage bus connectable to a load, a low voltage bus connectable to the load such that the load is in series between the high voltage bus and the low voltage bus, at least two capacitors having a fixed value of capacitance selectively connectable between the high voltage bus and the low voltage bus and a plurality of solid state switches equal in number to the number of capacitors having a fixed value of capacitance connectable between the high voltage bus and the low voltage bus, each switch configured and arranged to selectively connect or disconnect one of the capacitors having a fixed value of capacitance selectively connectable between the high voltage bus and the low voltage bus into electrical communication between the high voltage bus and the low voltage bus, and a variable frequency power supply including a high voltage output connection, the high voltage connection connected to the high voltage bus.

An ultrasonic device may include an electromechanical ultrasonic system defined by a predetermined resonant frequency and include an ultrasonic transducer coupled to an ultrasonic blade. A method of delivering energy to the device may include applying energy to the blade at a first power level via the transducer coupled to the blade, measuring a complex impedance of the transducer, receiving a complex impedance feedback data point, comparing the complex impedance feedback data point to a reference complex impedance characteristic pattern, and determining that the blade is contacting a vessel based on the comparison. The method may also include disabling the power applied to the transducer and switching to a lower power level. The method may further include generating a warning that the blade is contacting a vessel, such as a light or a sound. An ultrasonic surgical instrument may effect the method.

An acoustic filter device for telecommunication devices includes a first acoustic band pass filter having a corresponding first passband and a second acoustic band pass filter having a corresponding second passband. The second acoustic band pass filter is connected in parallel with the first acoustic band pass filter to provide a combined passband including the first and second passbands.

In an elastic wave filter device, a first filter including a first pass band and a second filter including a second pass band are common-connected at a common connection point. The first filter includes, on the common connection point side, a serial arm resonator, a parallel arm resonator, or a longitudinally coupled resonator-type elastic wave filter, and generates a fundamental wave and a high-order mode. A resonant frequency of the high-order mode on a higher frequency side relative to the first pass band of the first filter is smaller than the second pass band. On the common connection point side, a serial arm resonator in which the resonant frequency is not the highest, a parallel arm resonator, or a longitudinally coupled resonator-type elastic wave filter, is disposed.

In accordance with an embodiment, an RF system includes a transmit path having a first tunable transmit band stop filter, and a power amplifier coupled to an output of the first tunable transmit band stop filter, where the first tunable transmit band stop filter is configured reject a receive frequency and pass a transmit frequency; a receive path comprising an LNA; and a duplex filter having a transmit path port coupled to an output of the power amplifier, a receive path port coupled to an input of the LNA, and an antenna port, where the duplex filter is configured to pass the transmit frequency and reject the receive frequency between the antenna port and the transmit path port, pass the receive frequency and reject the transmit frequency between the antenna port and the receive path port.