An impedance adjustment device includes a variable capacitor unit. A microcomputer changes the capacitance value of the variable capacitor unit by switching PIN diodes included in n capacitor circuits on or off separately. Thus, the impedance on the plasma generator side when viewed from a high frequency power supply is adjusted. When changing the capacitance value of the variable capacitor unit to a target capacitance value, the microcomputer changes the capacitance value. When a predetermined period passes after the change of the capacitance value, the microcomputer changes the capacitance value again.

An exponentially-scaling switched impedance circuit includes: two or more impedance scaling circuits, wherein each impedance scaling circuit comprises: an input port; an output port; and a switched impedance circuit connected in parallel to the output port. Each impedance scaling circuit is configured to provide an effective impedance at the input port corresponding to a scaled-down version of the exponentially-scaling switched impedance circuit. The two or more impedance scaling circuits are connected in a cascade such that an input of an impedance scaling circuit is connected to an output of a previous impedance scaling circuit and/or an output of the impedance scaling circuit is connected to an input of a next impedance scaling circuit.

A transformer includes: a rotary shaft configured to rotate about a central axis of the rotary shaft as a rotational axis; a primary-side first coil configured to extend around a first axis perpendicular to the central axis; a secondary-side second coil configured to extend around a second axis and supported by the rotary shaft, the second axis being perpendicular to the rotational axis in an area surrounded by the first coil; and a secondary-side third coil configured to extend around a third axis and supported by the rotary shaft, the third axis being perpendicular to the rotational axis and forming a predetermined angle with the second axis in the area.

A tapped transmission line for distributing an electrical signal, such as an RF signal, to multiple modules, and/or aggregating signals from multiple modules. Embodiments of the invention provide a tapped transmission line based on a transmission-line medium along which tap elements are dispersed, so that the tap elements have a predominantly capacitive loading of the transmission-line medium. Methods for compensating the loss of the transmission-line medium are presented as well. Applications for distribution of transmitted signals, of local oscillator signals, and to aggregation of signals from multiple oscillators are disclosed. The invention is particularly applicable to integrated circuits (IC, ASIC, RFIC), and to multichannel RF systems such as phased array and MIMO systems.

One example includes a printed circuit board (PCB) structure. The PCB structure includes a first dereferenced microstrip and a first capacitor pad contacting the first dereferenced microstrip. The PCB structure includes a second dereferenced microstrip and a second capacitor pad contacting the second dereferenced microstrip. The PCB structure also includes a capacitor including a first terminal contacting the first capacitor pad and a second terminal contacting the second capacitor pad.

A wide band radio frequency (RF) circulator is presented. The RF circulator includes at least one stage having four ports, a first end, and a second end, wherein a first port and a third port are connected at the first end of the at least one stage, wherein a second port and a fourth port are connected at the second end of the at least one stage, wherein each of the at least one stage includes a pair of couplers connected through a first delay line and a second delay line, thereby forming a network of couplers in the at least one stage.

Input/output terminals 6a, 6b and 6c are formed within portions of cutouts 5a, 5b and 5c provided in a ground conductor 5 on the underside of a magnetic material 3; signal conductors 9a, 9b and 9c are formed within portions of cutouts 8a, 8b and 8c provided in a ground conductor 8 on the top surface of a dielectric substrate 7 at the same places as the cutouts 5a, 5b and 5c of the ground conductor; through holes 10a, 10b and 10c electrically connect a center conductor 4 to the input/output terminals 6a, 6b and 6c; metal bumps 11a, 11b and 11c electrically connect the input/output terminals 6a, 6b and 6c to the signal conductors 9a, 9b and 9c facing each other; and metal bumps 16 electrically connect the ground conductor 5 to the ground conductor 8.

Systems and methods for suppressing electrical noise in an electrocardiogram (ECG) signal obtained by at least one electrode and displayed on an ECG monitor are disclosed. The system includes a conductive material distinct from the at least one electrode and configured to contact a surface of a patient, and filtering circuitry connected in series between the conductive material and ground. The filtering circuitry may be configured to filter to ground the electrical noise present within the patient before it is received by the at least one electrode and is prevented from distorting the ECG signal that is displayed on the ECG monitor.

A balun includes a first winding which has a first terminal coupled to an input, and a second terminal coupled to a reference potential terminal. The balun includes a second winding magnetically coupled to the first winding. The second winding has a first terminal coupled to a first differential output, a second terminal coupled to a second differential output, and a tap coupled to the reference potential terminal. The balun includes a first capacitor which has a first terminal coupled to the first winding and a second terminal coupled to the second winding. The balun includes a third winding which has a first terminal coupled to the reference potential terminal and a floating second terminal. The balun includes a second capacitor which has a first terminal coupled to the third winding and a second terminal coupled to the second winding.

Methods and apparatus for a signal isolator having reduced parasitics. An example embodiment, a signal isolator and include a first metal region electrically connected to a first die portion, a second die portion isolated from the first die portion, and a second metal region electrically connected to the second die portion. A third metal region can be electrically isolated from the first and second metal regions and a third die portion can be electrically isolated from the first, second and third metal regions. In embodiments, the first metal region, the second metal region, and the third metal region provide a first isolated signal path from the first die portion to the second die portion.