Abstract: An overdrive topology structure for transmission of a RGB signal includes a signal sending terminal, a signal receiving terminal, and a transmission line to transmit the RGB signal from the signal sending terminal to the signal receiving terminal. The transmission line is divided into a number of section transmission lines. A node is formed between every two section transmission lines. An impedance of a first section transmission line approaching to the signal sending terminal is less than an impedance of a second section transmission line approaching to the first section transmission line to overdrive the RGB signal at a first node between the first and second section transmission lines. At least one node except the first node is grounded via a resistor. An equivalent resistance of the resistor is equal to a resistance of the first resistor.

Abstract: A differential signal transmission device transmits N differential signal pairs from a differential signal generator to a number of receiving terminals. The N differential signal pairs include N positive signals and N negative signals. The N positive signals are clustered at a first positive clustering point. The first positive clustering point is connected to a second positive clustering point via a first matching resistor. The second positive clustering point is grounded via a first grounding resistor, and outputs a number of positive signals to the number of receiving terminals respectively. The N negative signals are clustered at a first negative clustering point. The first negative clustering point is connected to a second negative clustering point via a second matching resistor. The second negative signal clustering point is grounded via a second grounding resistor, and outputs a number of negative signals to the number of receiving terminals respectively.

Abstract: A printed circuit board (PCB) with compound via includes a substrate and a pair of through holes passing through the substrate. The substrate includes a signal layer which is the top layer of the substrate, a first reference layer adjacent to the signal layer, and a second reference layer not adjacent to the signal layer. A first and a second pair of pads are mounted on the signal layer. Each of the through holes extends through the first pair of pads such that the through hole and the first pair of pads jointly form a compound via. A first reserved opening is formed on the first reference layer and corresponds to the first and the second pair of pads and the compound via. A second reserved opening is formed on the second reference layer and surrounds the through hole thereon.

Abstract: A printed circuit board (PCB) with compound via includes a substrate and a pair of through holes passing through the substrate. The substrate includes a signal layer which is the top layer of the substrate, a first reference layer adjacent to the signal layer, and a second reference layer not adjacent to the signal layer. A first and a second pair of pads are mounted on the signal layer. Each of the through holes extends through the first pair of pads such that the through hole and the first pair of pads jointly form a compound via. A first reserved opening is formed on the first reference layer and corresponds to the first and the second pair of pads and the compound via. A second reserved opening is formed on the second reference layer and surrounds the through hole thereon.

Abstract: A printed circuit board is constructed from various woven fiberglass fabrics, strengthened and bound together with epoxy resin, and includes a signal layer. The signal layer includes a positive differential signal line and a negative differential signal line laid out in parallel following a zig-zag pattern. A first distance and a second distance is designed at a ratio of 1:7. The first distance is a perpendicular distance between a highest point of the negative differential signal line and a reference line formed by connecting all lowest points of the negative differential signal line. The second distance is a perpendicular distance between a lowest point and an adjacent highest point of the negative differential signal line along the direction of the reference line.

Abstract: An electronic device includes a multi-frequency antenna. The multi-frequency antenna includes a ground portion, a support body, a radiation portion, and a strap. The ground portion defines a gap, and two grooves communicating with the gap and located at opposite ends of the gap. The radiation portion resists against a sidewall bounding the gap, and is connected to the strap. The radiation portion is accommodated in the gap and substantially coplanar with the ground portion. The radiation portion defines a slot. The support body is located in the gap and on the radiation portion, to support the strap.

Abstract: A differential signal transmission device transmits N differential signal pairs from a differential signal generator to a number of receiving terminals. The N differential signal pairs include N positive signals and N negative signals. The N positive signals are clustered at a first positive clustering point. The first positive clustering point is connected to a second positive clustering point via a first matching resistor. The second positive clustering point is grounded via a first grounding resistor, and outputs a number of positive signals to the number of receiving terminals respectively. The N negative signals are clustered at a first negative clustering point. The first negative clustering point is connected to a second negative clustering point via a second matching resistor. The second negative signal clustering point is grounded via a second grounding resistor, and outputs a number of negative signals to the number of receiving terminals respectively.

Abstract: An overdrive topology structure for transmission of a RGB signal includes a signal sending terminal, a signal receiving terminal, and a transmission line to transmit the RGB signal from the signal sending terminal to the signal receiving terminal. The transmission line is divided into a number of section transmission lines. A node is formed between every two section transmission lines. An impedance of a first section transmission line approaching to the signal sending terminal is less than an impedance of a second section transmission line approaching to the first section transmission line to overdrive the RGB signal at a first node between the first and second section transmission lines. At least one node except the first node is grounded via a resistor. An equivalent resistance of the resistor is equal to a resistance of the first resistor.

Abstract: An electronic device includes a multi-frequency antenna. The multi-frequency antenna includes a ground portion, a support body, a radiation portion, and a strap. The ground portion defines a gap, and two grooves communicating with the gap and located at opposite ends of the gap. The radiation portion resists against a sidewall bounding the gap, and is connected to the strap. The radiation portion is accommodated in the gap and substantially coplanar with the ground portion. The radiation portion defines a slot. The support body is located in the gap and on the radiation portion, to support the strap.