Abstract: The present invention is related to an electromagnetic noise filter device and an equivalent filter circuit thereof. The filter device comprises a substrate, a transmission line and a ground plane having slotted ground structure. The transmission line is configured on the top surface of the substrate, and the grounding plane is configured on the bottom surface of the substrate. At least one pair of impedance elements are configured within the slotted ground structure. The transmission line can be electromagnetic coupled to the slotted ground structure and the impedance elements so as to form an equivalent filter circuit. Thereby, the electromagnetic noises on at least one specific frequency may be absorbed by the impedance elements of the filter device so as to avoid the electromagnetic reflection induced by the electromagnetic noise and interfering the signal transmitted on the transmission line.

Abstract: A common mode noise reduction circuit includes at least one first input end, at least one second input end, at least one first output end, and at least one second output end. The circuit is further provided with at least one resistor, at least one inductor, and at least one capacitor, symmetrically disposed within the circuit loop defined by the four ends. Common mode noise, after entering the circuit, is transformed into heat by the resistance of the circuit such that the common mode noise is suppressed. Differential mode signals, on the contrary, after entering the circuit, can pass through the circuit with minimum loss.

Abstract: An all-pass filtering module of a common mode noise suppressing device includes first and second differential transmission circuits coupled to a reference node. Each of the first and second differential transmission circuits has an input terminal and an output terminal, and includes: first and second capacitive elements coupled in series between the input terminal and the output terminal; a first inductor coupled between the input terminal and the output terminal; and a third capacitive element and a second inductor coupled in series between the reference node and a common node between the first and second capacitive elements.

Abstract: A common mode noise reduction circuit includes at least one first input end, at least one second input end, at least one first output end, and at least one second output end. The circuit is further provided with at least one resistor, at least one inductor, and at least one capacitor, symmetrically disposed within the circuit loop defined by the four ends. Common mode noise, after entering the circuit, is transformed into heat by the resistance of the circuit such that the common mode noise is suppressed. Differential mode signals, on the contrary, after entering the circuit, can pass through the circuit with minimum loss.

Abstract: An electromagnetic bandgap (EBG) cell comprises a plurality of first conductive line layers beneath a first integrated circuit (IC) die, wherein wires on at least one of the first conductive line layers are each connected to one of a high voltage source and a low voltage source and are oriented to form a first mesh structure at a bottom of the EBG cell. The EBG cell further comprises a pair of through-substrate-vias (TSVs) above the plurality of first conductive line layers, wherein the pair of TSVs penetrate the first IC die and are connected to a high voltage source and a low voltage source, respectively, and a pair of micro bumps above a dielectric layer above the pair of TSVs, wherein the micro bumps connect the TSVs of the first IC die with a plurality of second conductive line layers formed on a second IC die.

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: 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: 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: The present invention is related to a filtering device with slotted ground structure, comprising a first substrate, a second substrate and a pair of differential signal lines, in which a ground plane having slotted ground structure is provided between the first substrate and the second substrate. Each of the two differential signal lines is symmetric to each other and comprises a first line segment being horizontally provided on the top surface of the first substrate and a second line segment being horizontally provided on the bottom surface of the second substrate, respectively. The first line segment is connected to the second line segment through a vertically disposed conductive via. Thereby, a common-mode noise within a specific frequency band may be suppressed effectively, so as to avoid interference a differential-mode signal transmitted on the differential signal lines, due to the slotted ground structure etched on the ground plane.

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 a frequency scope of several GHz without affecting the differential mode signals and improves manufacturing process miniaturization to decrease cost.

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: An exemplary embodiment of the present disclosure illustrates a signal transmission cell having a first through third conductors, a capacitor and an inductor. The first and third conductors form a first transmission circuit, and the second and the third conductors form a second transmission circuit. Signals which are respectively conveyed on the first transmission circuit and the second transmission circuit have the same magnitude, but have the opposite phases to each other, so as to form a pair of differential transmission lines. A first end of the inductor is electrically connected to the third conductor, and a second end of the inductor is electrically connected to a ground voltage. A first end of the capacitor is electrically connected to the first end of the inductor, and a second end of the capacitor is electrically connected to the second end the inductor.

Abstract: The present invention provides a device for suppressing common-mode radiation comprising: at least one resonator embedded into a plate, wherein the at least one resonator defines a plane having a normal direction parallel and perpendicular, respectively, to a longitudinal direction and a thickness direction of the plate. The embedment of the resonator into the plate enables a magnetic field, which is generated by a cable conductor when the device for suppressing common-mode radiation wraps the cable conductor therein, to perpendicularly pass through the plane so that the magnetic field and the resonator resonate together to generate a strong diamagnetism and thereby to suppress the common-mode radiation.

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 laterally extending member and a vertically extending member. The laterally extending member is parallel to the defected metal layer and a distance is maintained away from the defected metal layer. The projection area of the laterally extending member on the defected metal layer covers a length of the line-shaped opening corresponding to the laterally extending member. The vertically extending member connects the laterally extending member and the grounded metal layer.

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 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.