Signal Transmission System

Abstract

The signal transmission system 10 includes a wiring conductor (3) formed in an elliptical shape and having two focal points (3a, 3b), a GND conductor plate (4) arranged opposite the wiring conductor (3), a driver (1) connected between one focal point (3a) of the wiring conductor (3) and the GND conductor plate (4), a plurality of receivers (2a, 2b, 2c) connected between the wiring conductor (3) and the GND conductor plate (4), and a termination circuit (5) connected between the other focal point (3b) of the wiring conductor (3) and the GND conductor plate (4).

Description

[Technical field]

[0001] The present disclosure relates to a signal transmission system. [Background technology]

[0002] Some signal transmission systems applied to printed circuit boards connect a driver IC and a receiver IC with wiring, and provide a termination resistor (or termination circuit) near the receiver IC. When a bus wiring method consisting of a main line and a branch line is adopted for such a signal transmission system, the signal input from the main line to the branch line may be repeatedly reflected at the branch point or within the branch line. For this reason, the signal waveform becomes distorted due to the effects of multiple reflections, and the signal quality deteriorates. As a result, normal signal transmission becomes difficult.

[0003] As a countermeasure to this problem, a technique of inserting a resistor into the branch line has been proposed. Such a conventional signal transmission system is disclosed in, for example, Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-4263 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the signal transmission system disclosed in Patent Document 1, multiple reflections of a signal are suppressed by resistors, so that the signal amplitude becomes smaller as the number of branch lines increases (as the number of receiver ICs increases).

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a signal transmission system that can eliminate multiple reflections and suppress a decrease in the amplitude of a received signal, even when multiple receivers are provided for one driver. [Means for solving the problem]

[0007] The signal transmission system according to the present disclosure comprises: A plate-shaped ellipse with two foci on its periphery. The antenna comprises a wiring conductor, a ground conductor arranged opposite the wiring conductor, a driver connected between one focus of the wiring conductor and the ground conductor, a plurality of receivers connected between the wiring conductor and the ground conductor, and a termination circuit connected between the other focus of the wiring conductor and the ground conductor. Effect of the Invention

[0008] According to the present disclosure, even when multiple receivers are provided for one driver, it is possible to eliminate multiple reflections and suppress a decrease in the amplitude of a received signal. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic configuration diagram of a signal transmission system according to a first embodiment. [Diagram 2] 2A is a schematic diagram showing a driver connection structure, and FIG 2B is a cross-sectional view taken along line II-II of FIG 2A. [Diagram 3] FIG. 2 is a plan view showing a state of signal transmission. [Figure 4] FIG. 11 is a schematic configuration diagram of a signal transmission system according to a second embodiment. [Diagram 5] FIG. 11 is a schematic configuration diagram of a signal transmission system according to a third embodiment. [Figure 6] FIG. 1 is a schematic diagram of a conventional signal transmission system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] In order to describe the present disclosure in more detail, embodiments of the present disclosure will be described below with reference to the accompanying drawings.

[0011] Embodiment 1 A signal transmission system 10 according to a first embodiment will be described with reference to FIGS. 1 to 3. FIG.

[0012] First, before describing the signal transmission system 10 according to the first embodiment, a general signal transmission system 50 applied to a printed circuit board will be described with reference to Fig. 6. Fig. 6 is a schematic configuration diagram of a conventional signal transmission system 50.

[0013] 6, the signal transmission system 50 includes a driver 51, a receiver 52, a wiring conductor 53, a GND conductor plate 54, and a termination circuit 55. Such a signal transmission system 50 is provided on, for example, a printed circuit board (not shown).

[0014] Specifically, a driver 51 and a receiver 52 are mounted on the surface of a printed circuit board (not shown). The driver 51 and the receiver 52 are, for example, integrated circuits such as ICs (Integrated Circuits). The driver 51 and the receiver 52 are connected by a linear wiring conductor 53. A GND conductor plate 54 is disposed below the wiring conductor 53. A dielectric (not shown) is interposed between the wiring conductor 53 and the GND conductor plate 54. In addition, a termination circuit 55 is mounted on the wiring conductor 53 in close proximity to the receiver 52. The termination circuit 55 connects the wiring conductor 53 and the GND conductor plate 54.

[0015] The termination circuit 55 may be built into the receiver 52. The termination circuit 55 is, for example, a termination resistor.

[0016] Therefore, the signal output from the driver 51 travels through the wiring conductor 53 and then reaches the receiver 52 and the termination circuit 55. The termination circuit 55 absorbs the signal to suppress signal degradation due to multiple reflections. The termination circuit 55 also detects the voltage amplitude of the signal received by the receiver 52. Therefore, the signal transmission system 50 enables good signal transmission between the driver 51 and the receiver 52 without the generation of reflected waves.

[0017] Here, when a signal transmission method that enables a signal to be transmitted from one driver 51 to multiple receivers 52 is adopted in the signal transmission system 50, there is a risk of signal reflection occurring at a branching portion of the wiring conductor 53. When signal reflection occurs in this way, the quality of the signal is degraded, and the amplitude of the signal is reduced as the number of termination circuits 55 increases. In order to solve this problem, it is conceivable to reduce the number of termination circuits 55. However, if the number of termination circuits 55 is reduced, the signal is reflected at the end of the wiring to which the receiver 52 is connected, resulting in a significant reduction in signal quality.

[0018] 1, a signal transmission system 10 according to the first embodiment includes one driver 1, multiple receivers 2a, 2b, and 2c, a wiring conductor 3, a GND conductor plate (ground conductor) 4, and a termination circuit 5. Such a signal transmission system 10 is provided on, for example, a printed circuit board.

[0019] Specifically, the driver 1, the receivers 2a, 2b, and 2c, and the termination circuit 5 are connected between the wiring conductor 3 and the GND conductor plate 4. The wiring conductor 3 and the GND conductor plate 4 are disposed so as to face each other.

[0020] That is, one end of the driver 1 is connected to the wiring conductor 3, while the other end of the driver 1 is connected to a GND conductor plate 4. One ends of the receivers 2a, 2b, and 2c are connected to the wiring conductor 3, while the other ends of the receivers 2a, 2b, and 2c are connected to the GND conductor plate 4. One end of the termination circuit 5 is connected to the wiring conductor 3, while the other end of the termination circuit 5 is connected to the GND conductor plate 4.

[0021] The driver 1 and the receivers 2a, 2b, and 2c are, for example, integrated circuits such as ICs (Integrated Circuits). Fig. 1 shows an example of a signal transmission system 10 including three receivers 2a, 2b, and 2c. The number of receivers may be two or more.

[0022] The wiring conductor 3 is a flat conductor having an elliptical shape. The wiring conductor 3 has two focal points 3a and 3b. One end of the driver 1 is connected to one focal point 3a of the wiring conductor 3. One end of the termination circuit 5 is connected to the other focal point 3b of the wiring conductor 3. In addition, one ends of the receivers 2a, 2b, and 2c are connected to an outer peripheral portion 3c of the wiring conductor 3. The connection position of one end of the receivers 2a, 2b, and 2c to the wiring conductor 3 may be any position as long as it is the outer peripheral portion 3c.

[0023] The GND conductor plate 4 is disposed below the wiring conductor 3. The wiring conductor 3 and the GND conductor plate 4 are disposed parallel to each other. A dielectric (not shown) is interposed between the wiring conductor 3 and the GND conductor plate 4. The GND conductor plate 4 has the same elliptical shape and size as the wiring conductor 3. The GND conductor plate 4 may be any size as long as it is equal to or larger than the wiring conductor 3.

[0024] In Fig. 1, the driver 1, the receivers 2a, 2b, 2c, and the termination circuit 5 are illustrated as being disposed between the wiring conductor 3 and the GND conductor plate 4, but in reality, they have the connection structure shown in Fig. 2. Since the connection structures of the driver 1, the receivers 2a, 2b, 2c, and the termination circuit 5 are the same, Fig. 2 illustrates the connection structure of the driver 1 as a representative thereof.

[0025] As shown in Fig. 2, the driver 1 is provided on the wiring conductor 3. One terminal of the driver 1 is connected to one focal point 3a. The other terminal of the driver 1 is connected to the GND conductor plate 4 through a via 6. The via 6 reaches the GND conductor plate 4 through a through hole 3d formed in the wiring conductor 3. At this time, the via 6 is not in contact with the through hole 3d.

[0026] Therefore, as shown in FIG. 3, the signal output from the driver 1 is diffused in all directions inside the parallel plate consisting of the wiring conductor 3 and the GND conductor plate 4. At this time, since the parallel plate is elliptical, the signal diffused inside the elliptical plate is reflected once at its outer periphery and then converges to the other focal point 3b. Since a termination circuit 5 is provided at this focal point 3b, all of the signal is absorbed by the termination circuit 5. In this way, the signal is reflected once at the outer periphery 3c of the wiring conductor 3 (parallel plate). Therefore, the receivers 2a, 2c, and 2b connected to the outer periphery 3c do not receive multiple reflections of the signal.

[0027] Therefore, the signal transmission system 10 can realize good signal transmission without being affected by multiple reflections even if the signal transmission system has multiple receivers 2a, 2b, and 2c for one driver 1. Furthermore, even if the number of receivers 2a, 2b, and 2c increases, the signal transmission system 10 can suppress a decrease in the amplitude of the received signal because the termination circuit 5 remains one. Furthermore, the signal transmission system 10 does not require a complex control circuit, etc., so that the manufacturing cost can be suppressed.

[0028] In the signal transmission system 10, the outer periphery 3c of the wiring conductor 3 and the outer periphery of the GND conductor plate 4 may be connected by a plurality of vias. In this case, the signal is a modulated signal that does not contain a DC component, and the receivers 2a, 2b, and 2c are capable of detecting the current value of the modulated signal. Therefore, the signal transmission system 10 can reduce unwanted radiation from the side surface of the parallel plate.

[0029] Furthermore, the signal transmission system 10 can be applied not only to substrates but also to cloth, sheets, and the like.

[0030] As described above, even when the signal transmission system 10 according to the first embodiment includes a plurality of receivers 2a, 2b, and 2c for one driver 1, it is possible to eliminate multiple reflections and suppress a decrease in the amplitude of a received signal.

[0031] Embodiment 2 A signal transmission system 20 according to the second embodiment will be described with reference to FIG.

[0032] In the signal transmission system 10 according to the first embodiment, all the receivers 2a, 2b, and 2c are connected to the outer peripheral edge portion 3c of the elliptical wiring conductor 3. In contrast, as shown in Fig. 4, in the signal transmission system 20 according to the second embodiment, all the receivers 2a, 2b, and 2c are connected to the inside of the outer peripheral edge portion 3c of the elliptical wiring conductor 3.

[0033] Therefore, the signal output from the driver 1 is diffused in all directions inside the parallel plate consisting of the wiring conductor 3 and the GND conductor plate 4. At this time, since the parallel plate is elliptical, the signal diffused inside the elliptical plate is reflected once at its outer periphery and then converges to the other focal point 3b. Since the termination circuit 5 is provided at this focal point 3b, all of the signal is absorbed by the termination circuit 5. In this way, the signal is reflected once at the outer periphery 3c of the wiring conductor 3 (parallel plate). Therefore, the receivers 2a, 2c, and 2b connected to the inside of the outer periphery 3c do not receive multiple reflections of the signal.

[0034] As described 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 peripheral edge portion 3c of the wiring conductor 3, thereby significantly increasing the degree of freedom in arranging the receivers 2a, 2b, and 2c.

[0035] Embodiment 3 A signal transmission system 30 according to the third embodiment will be described with reference to FIG.

[0036] The signal transmission system 30 according to the third embodiment includes a driver 1 instead of the termination circuit 5 of the signal transmission system 10 according to the first embodiment. Of the drivers 1, the one connected to the focal point 3a is referred to as a first driver 1a, and the one connected to the focal point 3b is referred to as a second driver 1b.

[0037] The drivers 1a and 1b have the same input impedance as the input impedance of the termination circuit 5. Therefore, the driver 1b can operate as the termination circuit 5. Therefore, the drivers 1a and 1b can output a signal from either one of them.

[0038] As described above, the signal transmission system 30 of embodiment 3 can eliminate multiple reflections and suppress a decrease in the amplitude of the received signal even when multiple receivers 2a, 2b, and 2c are provided for one driver 1a or one driver 1b.

[0039] In addition, within the scope of the present disclosure, the embodiments may be freely combined, or any of the components in each embodiment may be modified, or any of the components in each embodiment may be omitted. [Industrial Applicability]

[0040] The device according to the present disclosure can be used in a device or the like. [Explanation of symbols]

[0041] 1, 1a, 1b driver; 2a, 2b, 2c receiver; 3 wiring conductor; 3a, 3b focal point; 3c outer periphery; 3d through hole; 4 GND conductor plate; 5 termination circuit; 10, 20, 30 signal transmission system.

Claims

1. A wiring conductor formed in an elliptical shape and having two foci, A ground conductor arranged to face the wiring conductor, A driver connected between one focus of the wiring conductor and the ground conductor, A plurality of receivers connected between the wiring conductor and the ground conductor, And a termination circuit connected between the other focus of the wiring conductor and the ground conductor. A signal transmission system characterized by the above.

2. The plurality of receivers are connected to the outer peripheral edge of the wiring conductor. The signal transmission system according to claim 1, characterized by the above.

3. The plurality of receivers are connected inside the outer peripheral edge of the wiring conductor. The signal transmission system according to claim 1, characterized by the above.

4. The termination circuit is a termination resistor. The signal transmission system according to claim 1, characterized by the above.

5. Instead of the termination circuit, a second driver is provided. The signal transmission system according to claim 1, characterized by the above.

6. It includes vias connecting between the outer peripheral edge of the wiring conductor and the outer peripheral edge of the ground conductor. The signal output from the driver is a modulated signal without a DC component. The plurality of receivers detect the current value of the modulated signal. The signal transmission system according to claim 1, characterized by the above.

7. The wiring conductor, the ground conductor, the driver, the receiver, and the termination circuit are mounted on one surface of a printed circuit board, cloth, or sheet. The signal transmission system according to any one of claims 1 to 6, characterized by the above.

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