SIGNAL TRANSMISSION SYSTEM

Abstract

A signal transmission system 10 comprises: a circuit conductor (3) which is elliptically shaped and has two focal points (3a, 3b); a GND circuit board (4) which is arranged opposite the circuit conductor (3); a driver (1) which is connected between a first focal point (3a) of the circuit conductor (3) and the GND circuit board (4); a plurality of receivers (2a, 2b, 2c) which are connected between the circuit conductor (3) and the GND circuit board (4); and a termination circuit (5) which is connected between a second focal point (3b) of the circuit conductor (3) and the GND circuit board (4).

Description

TECHNICAL AREA

[0001] The present disclosure relates to a signal transmission system. BACKGROUND ON THE STATE OF THE TECHNOLOGY

[0002] In a signal transmission system used for printed circuit boards, a driver IC and a receiver IC are connected by a wire, and a termination resistor (or termination circuit) is provided near the receiver IC. If a bus wiring scheme with a main line and a branch line is used for such a signal transmission system, a signal fed from the main line into a branch line will, in some cases, be repeatedly reflected at the branch point or within the branch line itself. This undesirable distortion of the signal waveform due to the effect of multiple reflections, degrading the signal quality. Consequently, achieving normal signal transmission becomes difficult.

[0003] As a countermeasure, a technology for inserting a resistor into a branch line was developed. Such a conventional signal transmission system is disclosed, for example, in patent literature 1. REFERENCE LIST PATENT LITERATURE

[0004] Patent Literature 1: JP H11-4263 A SUMMARY OF THE INVENTIONAL PROBLEM

[0005] However, since multiple reflections of signals are reduced by a resistor in the signal transmission system disclosed in patent literature 1, the amplitude of the signals decreases undesirably with an increasing number of branch lines (with an increasing number of receiver ICs).

[0006] The present disclosure was made to solve the problem described above, and one of its aims is to provide a signal transmission system that can eliminate multiple reflections and prevent the reduction of the amplitude of the received signals, even in a case where a plurality of receivers are included for a driver. TECHNICAL SOLUTION

[0007] A signal transmission system according to the present disclosure comprises: a circuit conductor that is elliptically shaped and has two focal points; an earthing conductor arranged opposite the circuit conductor; a driver connected between a first focal point of the focal points of the circuit conductor and the earthing conductor; a plurality of receivers connected between the circuit conductor and the earthing conductor; and a termination circuit connected between a second focal point of the focal points of the circuit conductor and the earthing conductor. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0008] The present disclosure can eliminate multiple reflections and prevent the reduction of the amplitude of the received signals, even when multiple receivers are present for a driver. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a schematic configuration diagram of a signal transmission system according to a first embodiment. Fig. 2A and Fig. Figure 2B shows schematic representations of the connection structure of a driver. Fig. 2A is a top view of the driver's connection structure. Fig. 2B is a cross-sectional view along a plane indicated by arrows II-II in Fig. 2A is shown. Fig. Figure 3 is a top view showing the state of signal transmission. Fig. Figure 4 is a schematic configuration diagram of a signal transmission system according to a second embodiment. Fig. Figure 5 is a schematic configuration diagram of a signal transmission system according to a third embodiment. Fig. Figure 6 is a schematic configuration diagram of a conventional signal transmission system. DESCRIPTION OF THE EXECUTION FORMS

[0009] The following sections, with reference to the attached drawings, explain ways of implementing the present disclosure in order to further clarify the present disclosure. First embodiment.

[0010] A signal transmission system 10 according to a first embodiment is based on Fig. 1 to Fig. 3 explained.

[0011] Before the signal transmission system 10 according to the first embodiment is explained, it will first be described using the following examples: Fig. 6 a typical signal transmission system 50 is explained, which is applied on a printed circuit board. Fig. Figure 6 is a schematic configuration diagram of the conventional signal transmission system 50.

[0012] As in Fig. As shown in Figure 6, the signal transmission system 50 comprises a driver 51, a receiver 52, a circuit conductor 53, a GND circuit board 54, and a termination circuit 55. Such a signal transmission system 50 is, for example, housed on a circuit board (not shown).

[0013] Specifically, the driver 51 and the receiver 52 are mounted on the surface of the printed circuit board (not shown). The driver 51 and the receiver 52 are integrated circuits, such as integrated circuits (ICs). The driver 51 and the receiver 52 are connected by the linear circuit conductor 53. The ground (GND) circuit board 54 is located below the circuit conductor 53. A dielectric (not shown) is inserted between the circuit conductor 53 and the GND circuit board 54. Furthermore, the termination circuit 55 is connected to the circuit conductor 53 near the receiver 52. The termination circuit 55 connects the circuit conductor 53 and the GND circuit board 54.

[0014] In some cases, the termination circuit 55 is built into the receiver 52. Furthermore, the termination circuit 5 is, for example, a terminating resistor.

[0015] Accordingly, an output signal from the driver 51 is transmitted via the circuit conductor 53 and subsequently reaches the receiver 52 and the termination circuit 55. By absorbing the signal, the termination circuit 55 reduces the signal degradation caused by multiple reflections. Furthermore, the termination circuit 55 detects the voltage amplitude of the signal received by the receiver 52. Thus, the signal transmission system 50 enables efficient signal transmission between the driver 51 and the receiver 52 without the occurrence of reflection waves.

[0016] If a signal transmission scheme is chosen for the signal transmission system 50 that allows the transmission of signals from a driver 51 to a multitude of receivers 52, signal reflections may occur at branch points on the circuit conductor 53. If signal reflections occur in this way, the signal quality decreases, and the signal amplitude is also undesirably reduced with an increasing number of termination circuits 55. To solve such problems, it is conceivable to reduce the number of termination circuits 55. However, if the number of termination circuits 55 is reduced, the signals are undesirably reflected at the line ends where the receivers 52 are connected, thus significantly reducing the signal quality.

[0017] In contrast, the signal transmission system 10 according to the first embodiment comprises, as in Fig. Figure 1 shows a driver 1, a plurality of receivers 2a, 2b and 2c, a circuit conductor 3, a GND circuit board (grounding conductor) 4 and a termination circuit 5. Such a signal transmission system 10 is, for example, housed on a circuit board.

[0018] The driver 1, the receivers 2a, 2b and 2c, and the termination circuit 5 are connected between the circuit conductor 3 and the GND circuit board 4. The circuit conductor 3 and the GND circuit board 4 are arranged facing each other.

[0019] This means that one end of driver 1 is connected to circuit conductor 3 and the other end of driver 1 is connected to the GND circuit board 4. The first ends of receivers 2a, 2b, and 2c are connected to circuit conductor 3, and the second ends of receivers 2a, 2b, and 2c are connected to the GND circuit board 4. One end of termination circuit 5 is connected to circuit conductor 3, and the other end of termination circuit 5 is connected to the GND circuit board 4.

[0020] It should be noted that driver 1 and receivers 2a, 2b, and 2c are integrated circuits, such as integrated circuits (ICs). Furthermore, it shows Fig. 1 An example of the signal transmission system 10 with the three receivers 2a, 2b and 2c. It is sufficient if the number of receivers is two or more.

[0021] Circuit conductor 3 is an elliptical flat conductor. Circuit conductor 3 has two focal points, 3a and 3b. The first end of driver 1 is connected to the first focal point, 3a, of circuit conductor 3. The first end of termination circuit 5 is connected to the second focal point, 3b, of circuit conductor 3. Furthermore, the first ends of receivers 2a, 2b, and 2c are connected to an outer circumferential edge, 3c, of circuit conductor 3. The positions at which the first ends of receivers 2a, 2b, and 2c are connected to circuit conductor 3 can be any position, as long as they are located on the outer circumferential edge, 3c.

[0022] The GND circuit board 4 is located below the circuit conductor 3. The circuit conductor 3 and the GND circuit board 4 are arranged parallel to each other. A dielectric (not shown) is inserted between the circuit conductor 3 and the GND circuit board 4. The GND circuit board 4 has an elliptical shape and a size that matches that of the circuit conductor 3. It is sufficient if the GND circuit board 4 is equal to or larger than the circuit conductor 3.

[0023] It should be noted that the driver 1, the receivers 2a, 2b and 2c and the termination circuit 5 in Fig. 1 are shown as being arranged between the circuit conductor 3 and the GND circuit board 4, but in fact the ones in Fig. The connection structures shown in the two diagrams are identical. The connection structures of the driver 1, the receivers 2a, 2b and 2c, and the termination circuit 5 are identical. Accordingly, in Fig. 2 The connection structure of driver 1 is shown representatively.

[0024] As in Fig. As shown in Figure 2, the driver 1 is mounted on the circuit conductor 3. One terminal of the driver 1 is connected to the first focal point 3a. The other terminal of the driver 1 is connected to the GND circuit board 4 via a through-hole 6. The through-hole 6 extends to the GND circuit board 4 through a through-hole 3d formed by the circuit conductor 3. At this point, the through-hole 6 is not in contact with the through-hole 3d.

[0025] Accordingly, as in Fig. Figure 3 shows the signals output by driver 1 scattered in all directions within a parallel flat plate containing circuit conductor 3 and the GND circuit board 4. Since the parallel flat plate is elliptical, the scattered signals are reflected once at the outer edge of the plate and then converge at a second focal point 3b. Because the termination circuit 5 is located at focal point 3b, all signals are absorbed by the termination circuit 5. In this way, signal reflections occur only once at the outer edge 3c of circuit conductor 3 (parallel flat plate). This prevents the receivers 2a, 2c, and 2b, which are connected to the outer edge 3c, from being struck by multiple signal reflections.

[0026] Therefore, the signal transmission system 10 can achieve efficient signal transmission without interference from multiple reflections, even in a signal transmission scheme containing multiple receivers 2a, 2b, and 2c for a single driver 1. Furthermore, since there is only one termination circuit 5, even as the number of receivers 2a, 2b, and 2c increases, the signal transmission system 10 prevents a reduction in the amplitude of the received signals. Since no complex control circuit or similar component is required, the signal transmission system 10 enables a reduction in manufacturing costs.

[0027] It should be noted that no problems arise even if the outer circumferential edge 3c of the circuit conductor 3 and the outer circumferential edge of the GND circuit board 4 are connected by a multitude of passes in the signal transmission system 10. In this case, the signals are assumed to be modulated signals without DC components, and the receivers 2a, 2b, and 2c can detect the current values ​​of the modulated signals. This allows the signal transmission system 10 to reduce unwanted radiation from the side surface of the parallel flat plate.

[0028] Furthermore, the signal transmission system 10 can be mounted not only on a plate, but also on a cloth, a film and the like.

[0029] As explained above, the signal transmission system 10 according to the first embodiment can eliminate multiple reflections and prevent the reduction of the amplitude of the received signals even when there are multiple receivers 2a, 2b and 2c for the one driver 1. Second embodiment.

[0030] A signal transmission system 20 according to a second embodiment is based on Fig. 4 explained.

[0031] In the signal transmission system 10 according to the first embodiment, all receivers 2a, 2b and 2c are connected to the outer circumferential edge 3c of the elliptical circuit conductor 3. In contrast, in the signal transmission system 20 according to the second embodiment, as in Fig. 4 shown, all receivers 2a, 2b and 2c connected to the inside of an outer circumferential edge 3c of an elliptical circuit conductor 3.

[0032] Accordingly, signals output by a driver 1 are distributed in all directions within a parallel flat plate containing the circuit conductor 3 and a GND circuit board 4. Since the parallel flat plate is elliptical, the signals scattered within the elliptical flat plate are reflected once at the outer edge of the plate and then converge at a second focal point 3b. Because a termination circuit 5 is provided at focal point 3b, all signals are absorbed by the termination circuit 5. In this way, signal reflections occur only once at the outer edge 3c of the circuit conductor 3 (parallel flat plate). This prevents the receivers 2a, 2c, and 2b connected on the inner side of the outer edge 3c from each receiving multiple signal reflections.

[0033] As explained above, in the signal transmission system 20 according to the second embodiment, the receivers 2a, 2b and 2c are connected to the inside of the outer circumferential edge 3c of the circuit conductor 3. This significantly increases the degree of freedom of the arrangement of the receivers 2a, 2b and 2c. Third embodiment.

[0034] A signal transmission system 30 according to a third embodiment is based on Fig. 5 explained.

[0035] The signal transmission system 30 according to the third embodiment includes a driver 1 instead of the termination circuit 5 in the signal transmission system 10 according to the first embodiment. It should be noted that one of the drivers 1 connected to a focal point 3a is treated as the first driver 1a and the other driver 1 connected to a focal point 3b is treated as the second driver 1b.

[0036] Drivers 1a and 1b have an input impedance that is identical to the input impedance of the termination circuit 5. Therefore, driver 1b can function as the termination circuit 5. Consequently, signals can be output by both driver 1a and driver 1b.

[0037] As explained above, the signal transmission system 30 according to the third embodiment can eliminate multiple reflections and prevent the reduction of the amplitude of the received signals, even when multiple receivers 2a, 2b and 2c are present for the one driver 1a or the one driver 1b.

[0038] It should be noted that the present disclosure permits any combination of embodiments, modifications of components of each embodiment, and the omission of components of each embodiment within the scope of the disclosure. INDUSTRIAL APPLICABILITY

[0039] The devices according to the present disclosure are suitable for use as or in devices and the like. REFERENCE MARK LIST

[0040] 1, 1a, 1b: Driver; 2a, 2b, 2c: Receiver; 3: Circuit conductor; 3a, 3b: Focal point; 3c: Outer circumferential edge; 3d: Through-hole; 4: GND circuit board; 5: Termination circuit; 10, 20, 30: Signal transmission system QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP H11-4263 A

[0004]

Claims

[1] Signal transmission system, comprising: an elliptically shaped circuit conductor that has two focal points; a grounding conductor that is arranged facing the circuit conductor; a driver connected between a first focal point of the circuit conductor and the ground conductor; a plurality of receivers connected between the circuit conductor and the grounding conductor; and a termination circuit that is connected between a second focal point of the circuit conductor and the grounding conductor. [2] Signal transmission system according to claim 1, wherein the plurality of receivers are connected to an outer circumferential edge of the circuit conductor. [3] Signal transmission system according to claim 1, wherein the plurality of receivers are connected to an inner side of an outer circumferential edge of the circuit conductor. [4] Signal transmission system according to any one of claims 1 to 3, wherein the termination circuit is a termination resistor. [5] Signal transmission system according to one of claims 1 to 4, wherein a second driver is provided instead of the termination circuit. [6] Signal transmission system according to one of claims 1 to 5, comprising a passage connecting an outer circumferential edge of the circuit conductor and an outer circumferential edge of the grounding conductor, wherein a signal output by the driver is a modulated signal that contains no DC component, and Most receivers capture a current value of the modulated signal. [7] Signal transmission system according to any one of claims 1 to 6, wherein the circuit conductor, the grounding conductor, the driver, the receivers and the termination circuit are implemented on a surface of a printed circuit board, a cloth or a sheet.

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