Abstract: A transmission line with a structure which is capable of forming a passive equalizer and an electrical apparatus using the same are illustrated. The transmission line has a substrate, a ground plane, a defect ground structure, a pair of transmission conducting lines, and at least one stub. The substrate has a plurality of surfaces. The ground plane is located on at least one of the surfaces. The defect ground structure is formed on the ground plane. The pair of transmission conducting lines is located on one of the surfaces, and stretching over the defect ground structure. The at least one stub is located above a plane of the defect ground structure, extending along with at least one side of two sides of the pair of the transmission conducting lines, and electrically coupled to the pair of the transmission conducting lines and the ground plane.

Abstract: Baluns with imaginary common-mode impedance are disclosed. A disclosed balun comprises an unbalanced port with an unbalanced terminal and a ground terminal, a balanced port with two balanced terminals opposite to each other in phase, and a transmission cell. The transmission cell has a differential transmission line, a virtually-ground patch, a ground conductor, and a conductive structure. The differential transmission line has a pair of conductive traces spaced apart from each other, and is electrically connected between the unbalanced port and the balanced port to transmit a differential signal. The virtually-ground patch is spaced apart from the differential transmission line. The conductive structure electrically connects the virtually-ground patch to the ground conductor.

Abstract: An exemplary embodiment of the present disclosure illustrates a multilayer circuit board structure, for suppressing the undesired electromagnetic wave propagation within a specific frequency band. The multilayer circuit board structure includes a plurality of crystals and a plurality of conducting channels, wherein a crystal includes a first through fourth conducting planes, at least a first conducting connector, and at least a second conducting connector, wherein the first through the fourth conducting planes are substantially parallel to each other. The first conducting plane is electrically connected to the third conducting plane through the first conducting connector. The fourth conducting plane is electrically connected to the second conducting plane through the second conducting connector. The first and the third conducting planes are configured to be electrically separated from the second and the fourth conducting planes.

Abstract: A transmission line with a structure which is capable of forming a passive equalizer and an electrical apparatus using the same are illustrated. The transmission line has a substrate, a ground plane, a defect ground structure, a pair of transmission conducting lines, and at least one stub. The substrate has a plurality of surfaces. The ground plane is located on at least one of the surfaces. The defect ground structure is formed on the ground plane. The pair of transmission conducting lines is located on one of the surfaces, and stretching over the defect ground structure. The at least one stub is located above a plane of the defect ground structure, extending along with at least one side of two sides of the pair of the transmission conducting lines, and electrically coupled to the pair of the transmission conducting lines and the ground plane.

Abstract: This invention provides a digital electronic device comprising: a grounded metal portion comprising a first metal plate electrically connected to ground and a first substrate disposed on the first metal plate; at least one layer of differential-mode reference metal portion comprising a second substrate and a second metal plate electrically connected to the first metal plate by at least one conductive structure; a pair of differential signal lines at least partially disposed on the second substrate of the at least one layer of differential-mode reference metal portion and electromagnetically coupled to the second metal plate of the at least one layer of differential-mode reference metal portion; and an equalizer electrically connected to the pair of differential signal lines.

Abstract: A filtering device is capable of suppressing common mode noises upon transmission of a differential signal, and includes a differential transmission line, a grounding layer, a dielectric unit and a conductive structure. The differential transmission line has a pair of conductive traces spaced apart from each other. The grounding layer is spaced apart from the differential transmission line. The dielectric unit is disposed between the differential transmission line and the grounding layer. The conductive structure is embedded in the dielectric unit, is coupled electrically to the conductive traces and the grounding layer, and cooperates with the differential transmission line, the grounding layer and the dielectric unit to form a stacked structure that has an effective negative permittivity, thereby suppressing the common mode noises coupled to the conductive traces. A differential signal transmission circuit is also disclosed.

Abstract: A noise filtering circuit for suppressing electromagnetic interference (EMI) is provided. The noise filtering circuit filters out high multiplied-frequency noise of a digital signal being transmitted and includes a reference voltage structure formed from conductors, a signal transmitting structure formed from a transmission conductor, a ground layer, and a ground structure electrically connected to the reference voltage structure and the ground layer. The ground structure is configured to form an inductor-capacitor oscillating structure in coordination with the electric-magnetical coupling between the reference voltage structure and the signal transmitting structure as well as the inductance of the ground structure, so that a digital signal is filtered out at a specific frequency and the passband of the digital signal can be transmitted.

Abstract: An electromagnetic noise suppression circuit is provided. The suppression circuit comprises a first substrate, a first grounding plane and at least one transmission line. The transmission line is configured on a top surface of the first substrate and the first grounding plane is configured on the bottom surface of the first substrate. The first grounding plane comprises a first distributed coupling structure. The first distributed coupling structure and the transmission line can be equivalent to an inductor-capacitor resonant circuit. The electromagnetic noise within a designated frequency band can be suppressed by the distributed coupling structure of the electromagnetic noise suppression circuit to avoid interfering the signal transmitted by the transmission line and the electromagnetic radiation induced by the electromagnetic noise.

Abstract: A method for reducing EM radiation comprises at least one first resonance line disposed on one of electric surfaces, which is disposed at a side of a transmission line structure on one of the electric surface. The resonance line crosses over a slot of another electric surface. The slot is etched on a corresponding electric surface. In addition, the transmission line structure crosses over the slot of the electric surface. Then, the first resonance line connects the electric surface having the slot with another electric surface. It can adjust at least one of a length, a width and a shape of the first resonance line, to make an input impedance seen from a crossed point between the transmission line structure and the slot approximately 0.

Abstract: A defected ground structure with shielding effect is provided. The structure includes a dielectric layer, a defected metal layer, a grounded metal layer and at least a conductive mushroom-like structure. The defected metal layer has a line-shaped opening and is disposed in the dielectric layer. The conductive mushroom-like structure is disposed between the defected metal layer and the grounded metal layer and is arranged along an extending direction of the line-shaped opening periodically. The conductive mushroom-like structure includes a fungating part and a stipe part. The fungating part is parallel to the defected metal layer and a distance is maintained away from the defected metal layer. The projection area of the fungating part on the defected metal layer covers a length of the line-shaped opening corresponding to the fungating part. The stipe part connects the fungating part and the grounded metal layer.

Abstract: The invention relates to an embedded multi-layer circuit board and a noise suppression method. The embedded multi-layer circuit board comprises at least two ground layers, a power layer and a plurality of vias. The power layer is between two ground layers. Each via is electrically connected with the two ground layers and electrically isolated from the power layer. The power layer is divided to a plurality of periodical cells. Each cell comprises the same number of the vias.

Abstract: Proposed is an apparatus for silencing electromagnetic noise, characterized by a plurality of centrally symmetrical ring-shaped through-via-hole crystalline units provided between a high voltage plane and a low voltage plane at a regular interval, thereby forming an omnidirectional noise suppression frequency band for reducing noise interference and electromagnetic radiation. In a first embodiment of the ring-shaped through-via-hole crystalline units, the through via holes are perpendicularly coupled between a metal plane and the low voltage plane. In a second embodiment of the ring-shaped through-via-hole crystalline units, the through via holes are perpendicularly coupled between two metal planes. Positioned at a regular interval, the through via holes enable provision of omnidirectional noise suppression frequency band, simplified design of a power plane, and reduction of production costs.

Abstract: A common mode noise suppression circuit applicable to differential signal transmission performs common mode noise suppression with respect to differential signals transmitted by a transmission line. An inductance-capacitance resonant structure is formed based on electromagnetic coupling combining a ground structure to suppress common mode noise of differential mode signals at broadband meanwhile keeping low loss of the differential mode signals at broadband via differential transmission lines. By this, the common mode noise suppression circuit performs broadband suppression with related to the common mode noise within frequency scope of several GHzs without affecting the differential mode signals and improves manufacturing process miniaturization to decrease cost.

Abstract: Provided are common mode filtering method and device for use with a defected ground structure, the device including a substrate, coupled microstrip lines formed on the substrate and a ground plane formed underneath the substrate, the common mode filtering method being characterized by forming at least a defected ground structure on the ground plane and making dual mode signals pass through the coupled microstrip lines, thereby using the defected ground structure to suppress dual model noises within a specific frequency band and prevent signal distortion.

Abstract: A filtering device is capable of suppressing common mode noises upon transmission of a differential signal, and includes a differential transmission line, a grounding layer, a dielectric unit and a conductive structure. The differential transmission line has a pair of conductive traces spaced apart from each other. The grounding layer is spaced apart from the differential transmission line. The dielectric unit is disposed between the differential transmission line and the grounding layer. The conductive structure is embedded in the dielectric unit, is coupled electrically to the conductive traces and the grounding layer, and cooperates with the differential transmission line, the grounding layer and the dielectric unit to form a stacked structure that has an effective negative permittivity, thereby suppressing the common mode noises coupled to the conductive traces. A differential signal transmission circuit is also disclosed.

Abstract: A circuit structure is provided. The circuit structure includes a capacitor including a top capacitor electrode; a bottom capacitor electrode parallel to the top capacitor electrode; and an insulating layer between the top and the bottom capacitor electrodes. The insulating layer includes a dielectric rod enclosed by a dielectric material. The dielectric rod has a higher dielectric constant than that of the dielectric material. The circuit structure may be a printed circuit board or packaging substrate, wherein the capacitor is formed between the two layers of the capacitor. Additional dielectric rods may be formed in the insulating layer of the capacitor and spaced apart from the dielectric rods.

Abstract: Provided are common mode filtering method and device for use with a defected ground structure, the device including a substrate, coupled microstrip lines formed on the substrate and a ground plane formed underneath the substrate, the common mode filtering method being characterized by forming at least a defected ground structure on the ground plane and making dual mode signals pass through the coupled microstrip lines, thereby using the defected ground structure to suppress dual model noises within a specific frequency band and prevent signal distortion.

Abstract: Proposed is an apparatus for silencing electromagnetic noise, characterized by a plurality of centrally symmetrical ring-shaped through-via-hole crystalline units provided between a high voltage plane and a low voltage plane at a regular interval, thereby forming an omnidirectional noise suppression frequency band for reducing noise interference and electromagnetic radiation. In a first embodiment of the ring-shaped through-via-hole crystalline units, the through via holes are perpendicularly coupled between a metal plane and the low voltage plane. In a second embodiment of the ring-shaped through-via-hole crystalline units, the through via holes are perpendicularly coupled between two metal planes. Positioned at a regular interval, the through via holes enable provision of omnidirectional noise suppression frequency band, simplified design of a power plane, and reduction of production costs.

Abstract: A circuit structure is provided. The circuit structure includes a capacitor including a top capacitor electrode; a bottom capacitor electrode parallel to the top capacitor electrode; and an insulating layer between the top and the bottom capacitor electrodes. The insulating layer includes a dielectric rod enclosed by a dielectric material. The dielectric rod has a higher dielectric constant than that of the dielectric material. The circuit structure may be a printed circuit board or packaging substrate, wherein the capacitor is formed between the two layers of the capacitor. Additional dielectric rods may be formed in the insulating layer of the capacitor and spaced apart from the dielectric rods.

Abstract: A substrate for circuits is provided in this invention. The substrate includes a first voltage reference plane, a second voltage reference plane, a first dielectric layer, and a plurality of second dielectric materials embedded in the first dielectric layer. The first dielectric layer is between the first and second voltage reference planes. Each of the plurality of second dielectric materials includes a first end contacted with the first voltage reference plane and a second end contacted with the second voltage reference plane. The dielectric constant of the first dielectric layer is different from the dielectric constant of the second dielectric materials.