An apparatus and method for receiving a magnetic resonance (MR) signal for imaging a patient. The MR signal includes a MR frequency. A radio frequency (RF) coil has first and second end portions. An impedance converter is in electrical communication with the RF coil. A preamplifier in electrical communication with the impedance converter, the preamplifier having a gain. At least one resonant circuit electrically connected to at least one end portion of the RF coil.

An apparatus and method for receiving a magnetic resonance (MR) signal for imaging a patient. The MR signal includes a MR frequency. A radio frequency (RF) coil has first and second end portions. An impedance converter is in electrical communication with the RF coil. A preamplifier in electrical communication with the impedance converter, the preamplifier having a gain. At least one resonant circuit electrically connected to at least one end portion of the RF coil.

A transformer of the symmetric-asymmetric type includes comprising a primary inductive circuit and a secondary inductive circuit formed in a same plane by respective interleaved and stacked metal tracks. A first crossing region includes a pair of connection plates facing one another, with each connection plate having a rectangular shape that is wider than the metal tracks, and diagonally connected to tracks of the secondary inductive circuit.

A transformer of the symmetric-asymmetric type includes comprising a primary inductive circuit and a secondary inductive circuit formed in a same plane by respective interleaved and stacked metal tracks. A first crossing region includes a pair of connection plates facing one another, with each connection plate having a rectangular shape that is wider than the metal tracks, and diagonally connected to tracks of the secondary inductive circuit.

An amplifier includes a first and a second differential input ports, and a single-ended output port. The amplifier includes a first and a second transistors, each having a gate, source, and drain terminals. The source terminals are coupled to a reference plane and the gate terminals are coupled to the respective first and second differential input ports. The amplifier includes a Balun having a primary and a secondary transformer winding, the primary transformer winding having one end coupled to the drain terminal of the first transistor, an opposite end coupled to the drain terminal of the second transistor, and a center tap coupled to a bias voltage, and the secondary transformer winding is adjacent to the primary transformer winding and having one end coupled to the single-ended output port and an opposite end open circuited. An electromagnetic field generated at the primary induces a signal at the secondary transformer winding.

An amplifier includes a first and a second differential input ports, and a single-ended output port. The amplifier includes a first and a second transistors, each having a gate, source, and drain terminals. The source terminals are coupled to a reference plane and the gate terminals are coupled to the respective first and second differential input ports. The amplifier includes a Balun having a primary and a secondary transformer winding, the primary transformer winding having one end coupled to the drain terminal of the first transistor, an opposite end coupled to the drain terminal of the second transistor, and a center tap coupled to a bias voltage, and the secondary transformer winding is adjacent to the primary transformer winding and having one end coupled to the single-ended output port and an opposite end open circuited. An electromagnetic field generated at the primary induces a signal at the secondary transformer winding.

A balun includes an unbalanced terminal; first and second balanced terminals; first and second main lines; first and second sub-lines; and a parallel line. The first main line has an end connected to the unbalanced terminal. The second main line has an end connected to another end of the first and second end that is open. The first sub-line is connected between the first and a reference potential, and is coupled to the first main line. The second sub-line is connected between the second balanced terminal and the reference potential, and is coupled to the second main line. The parallel line is connected in parallel with a part of the first sub-line. The line length of a specific portion of the first sub-line that is connected in parallel with the parallel line is different from the line length of the parallel line.

A balun includes an unbalanced terminal; first and second balanced terminals; first and second main lines; first and second sub-lines; and a parallel line. The first main line has an end connected to the unbalanced terminal. The second main line has an end connected to another end of the first and second end that is open. The first sub-line is connected between the first and a reference potential, and is coupled to the first main line. The second sub-line is connected between the second balanced terminal and the reference potential, and is coupled to the second main line. The parallel line is connected in parallel with a part of the first sub-line. The line length of a specific portion of the first sub-line that is connected in parallel with the parallel line is different from the line length of the parallel line.

Disclosed herein is a common mode filter that includes a winding core part and first and second wires wound in a same direction around the winding core part. The first and second wires constitute a first winding block on one endmost side in an axial direction of the winding core part, a second winding block on other endmost side in the axial direction of the winding core part, and a third winding block positioned between the first and second winding blocks. The second winding block is a winding block at an odd-numbered position counted from the first winding block. The first and second wires cross each other in an area between the first and third winding blocks and in an area between the second and third winding blocks.

A common mode choke coil is configured in which end portions of first and second wires are connected to first and second terminal electrodes, end portions of third and fourth wires are connected to third and fourth terminal electrodes, and at least a part of each of the first, third, fourth and second wires is wound around a winding core portion to form first, second, third and fourth layers. Also, a common mode choke coil is configured in which end portions of first and second wires are connected to first and second terminal electrodes, end portions of a third wire are connected to third and fourth terminal electrodes, and at least a part of each of the first, third, and second wires is wound around a winding core portion to form first, second, and third layers.