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 signal transmission apparatus used in a printed circuit board (PCB). The apparatus includes a differential pair composed of two transmission lines arranged side by side in the PCB. The differential pair includes a filter section arranged therein to filter noise of transmission signals of the differential pair. The filter includes a number of section pairs connected in series. Each section pair includes two sections arranged in the two transmission lines symmetrically. Every two adjacent sections are different in line width. A distance between the two transmission lines, and the line width of each of the sections are predetermined according to desired frequency bandwidth, and desired frequency response of the differential pair.

Abstract: A signal transmission apparatus includes two circuit layers. First and second ground sheets are arranged in the two circuit layers respectively. A third ground sheet is arranged between the two circuit layers. A differential pair includes a transmission line arranged between the first and third ground sheets and a transmission line arranged between the second and third ground sheets. The first to third ground sheets have same electric potential. Projections of the first and second ground sheets on the third ground sheet superpose a border of the third ground sheet. The third ground sheet is formed by extending the border along a signal transmission direction.

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 circuit topology for multiple loads includes a driving terminal for transmitting a driving signal, a number of transmitting lines, and a number of loads operable to receive the driving signal from the driving terminal. The number of loads are connected to the driving terminal one by one via the number of transmitting lines. Two transmitting lines of the number of transmitting lines, which are nearest and farthest respectively from the driving terminal, are both greater than widths of the other transmitting lines.

Abstract: A circuit topology for multiple loads includes a driving terminal for transmitting a driving signal, a number of transmitting lines, and a number of loads operable to receive the driving signal from the driving terminal. The number of loads are connected to the driving terminal one by one via the number of transmitting lines. Two transmitting lines of the number of transmitting lines, which are nearest and farthest respectively from the driving terminal, are both greater than widths of the other transmitting lines.