CN215818183U

CN215818183U - Ethernet transmission circuit

Info

Publication number: CN215818183U
Application number: CN202122285746.XU
Authority: CN
Inventors: 莫敏宁
Original assignee: Shenzhen Kunci Technology Co ltd
Current assignee: Shenzhen Kunci Technology Co ltd
Priority date: 2021-09-22
Filing date: 2021-09-22
Publication date: 2022-02-11
Anticipated expiration: 2031-09-22

Abstract

The application discloses ethernet transmission circuit, this ethernet transmission circuit includes four groups of subcircuits, and each group of subcircuit all includes coupling in the first capacitor of the first input end of subcircuit, coupling in the second capacitor of the second input end of subcircuit, and ethernet transformer. The ethernet transformer includes a first coil and a second coil. The first coil includes a first input contact coupled to the first capacitor, a first output contact coupled to a first output of the sub-circuit, and a first center tap coupled to ground. The second coil includes a second input contact, a second output contact, and a second center tap. The second input contact is coupled to the second capacitor, the second center tap is coupled to a second output terminal of the sub-circuit, and the second output contact is coupled to ground.

Description

Ethernet transmission circuit

Technical Field

The utility model relates to an Ethernet transmission circuit. Specifically, each set of ethernet transformers in the ethernet transmission circuit of the present invention can provide a voltage transformation effect for the signal transmission process between the ethernet chip and the ethernet connector through only one common mode inductor.

Background

In a conventional ethernet network, a set of ethernet transformers for signals is provided for each set of differential signals of the ethernet network, and the ethernet transformers need to achieve the effects of isolation, signal coupling and common mode filtering of input signals through a set of transformers composed of a common mode inductor and a capacitor and another common mode inductor. Since the above-mentioned arrangement of the ethernet transformer involves the participation of two common mode inductors, two magnetic cores have to be provided for the winding of the coil, and this results in a consequent increase in the area of the ethernet transformer itself, and even of the entire ethernet transmission circuit including said ethernet transformer. In view of the above, how to provide an ethernet transmission circuit with a smaller area and capable of maintaining the signal transformation effect in the ethernet is a problem to be solved in the art.

SUMMERY OF THE UTILITY MODEL

In order to solve at least the above problems, the present invention discloses an ethernet transmission circuit. The Ethernet transmission circuit comprises four groups of sub-circuits, and each group of sub-circuits comprises a first capacitor, a second capacitor and an Ethernet transformer. The first capacitor is coupled to a first input terminal of the sub-circuit. The second capacitor is coupled to a second input terminal of the sub-circuit. The ethernet transformer includes a first coil, a second coil, and a magnetic core, and the first coil and the second coil are wound around the magnetic core. The first coil includes a first input contact, a first output contact, and a first center tap. The first input contact is coupled to the first capacitor, the first center tap is coupled to a first output terminal of the sub-circuit, and the first output contact is coupled to ground. The second coil includes a second input contact, a second output contact, and a second center tap. The second input terminal is coupled to the second capacitor, the second center tap is coupled to a second output terminal of the sub-circuit, and the second output terminal is coupled to ground.

The main objects, technical means and embodiments of the present invention will be understood by those skilled in the art after referring to the accompanying drawings and the embodiments described later.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a schematic diagram of one implementation of an Ethernet transmission circuit of the present invention; and

FIG. 2 is a partially enlarged schematic diagram of an Ethernet transformer in the Ethernet transmission circuit of FIG. 1; and

fig. 3 is a schematic diagram of a winding pattern of a coil of an ethernet transformer in the ethernet transmission circuit shown in fig. 1.

Detailed Description

The following examples are provided to illustrate the technical content of the present invention and are not intended to limit the scope of the present invention. It should be noted that in the following embodiments and the accompanying drawings, elements irrelevant to the present invention are omitted and not shown, and the dimensional relationship between the elements in the drawings is only for easy understanding and is not intended to limit the actual scale.

Fig. 1 is a schematic diagram of an embodiment of an ethernet transmission circuit of the present invention. Referring to fig. 1, the ethernet transport circuit 1 may basically include four sets of

sub-circuits

11, 12, 13, 14 and may be coupled to an ethernet signal source (e.g., a physical layer device in an ethernet network). Since eight signals of the ethernet signal source can be equally divided into four groups of signals, the

sub-circuits

11, 12, 13, 14 can respectively correspond to one of the four groups of signals of the ethernet signal source. The

sub-circuits

11, 12, 13, 14 have substantially the same structure and the input and output types of the respective couplings are similar. Therefore, based on the principle of simplifying the description, only the sub-circuit 11 is taken as an example for illustration, but those skilled in the art can understand the corresponding structure and function of the

sub-circuits

12, 13, 14 according to the description of the sub-circuit 11.

The sub-circuit 11 may include a capacitor C1, a capacitor C2, and an ethernet transformer T1. The capacitor C1 may be coupled to the input IN1 of the sub-circuit 11, and the capacitor C2 may be coupled to the other input IN2 of the sub-circuit 11. The capacitor C1 and the capacitor C2 can provide signal coupling and dc isolation functions for the ethernet transmission circuit 1.

Fig. 2 is a partially enlarged schematic diagram of the ethernet transformer T1 in the ethernet transmission circuit 1 shown in fig. 1. Referring to fig. 1 and 2 together, the ethernet transformer T1 may include a coil L1, a coil L2, and a core M1, and the two coils are wound around the core M1. Coil L1 may include input contact IC1, output contact OC1, and center tap TA 1. Coil L2 may include input contact IC2, output contact OC2, and center tap TA 2. The center tap TA1 is coupled to the output terminal OUT1 of the sub-circuit 11. the center tap TA2 is coupled to the output terminal OUT2 of the sub-circuit 11. The output terminal OC1 of the coil L1 and the output terminal OC2 of the coil L2 are both coupled to ground.

Fig. 3 is a schematic diagram of a winding pattern of a coil of an ethernet transformer in the ethernet transmission circuit shown in fig. 1. Referring to fig. 1, 2 and 3 simultaneously, center tap TA1 can distinguish coil L1 into left half-coil LL1 and right half-coil RL 1. Similarly, center tap TA2 can distinguish coil L2 into left half-coil LL2 and right half-coil RL 2.

In coil L1, the left half-coil LL1 may be wound around core M1 in a different direction (e.g., clockwise or counterclockwise) than the right half-coil RL1 is wound around core M1. More specifically, as shown in fig. 3, in coil L1, the portion from output contact OC1 to center tap TA1 (i.e., left half-coil LL1) may be wound around core M1 in the counterclockwise direction, while the portion from center tap TA1 to input contact IC1 (i.e., right half-coil RL1) may be wound around core M1 in the opposite clockwise direction.

On the other hand, in the coil L2, the left half-coil LL2 may be wound around the magnetic core M1 in the same direction (e.g., clockwise direction) as the right half-coil RL2 is wound around the magnetic core M1. In some embodiments, left half-coil LL1 of coil L1 and left half-coil L2 of coil L2 may be wound around magnetic core M1 in opposite directions and with opposite slopes of the two coil windings, such that left half-coil LL1 and left half-coil LL2 are wound around magnetic core M1 for equal lengths.

The ethernet transformer T1 configured as described above may be used to perform common mode filtering on signals input from the input terminal IN1 and the input terminal IN 2. Noise outside a specific frequency band is filtered out. The common mode inductor CM2 may be used to provide a ground reference to avoid signal level offset at the output terminals OUT1 and OUT 2.

A set of ethernet signals processed by the sub-circuit 11 may be output from the output terminal OUT1 and the output terminal OUT2 to the ethernet connector. The ethernet connector may be an ethernet connector with an RJ-45 or 8P8C interface. As mentioned above, since the

sub-circuits

12, 13, 14 and the sub-circuit 11 are substantially the same, a person skilled in the art can understand how the

sub-circuits

12, 13, 14 output the processed three sets of ethernet signals to the ethernet connector in the same manner as the sub-circuit 11 according to the above description of the sub-circuit 11, and the details of the same are not repeated herein.

In summary, with the special arrangement of the ethernet transmission circuit 1 of the present invention, only one magnetic core is needed to provide the voltage transformation effect for signals in the ethernet. Therefore, compared with the traditional processing mode, the Ethernet transmission circuit of the utility model really reduces the required circuit area and simultaneously reduces the hardware setting cost of signal transformation in the Ethernet.

The above examples are only intended to illustrate the embodiments of the present invention and to illustrate the technical features of the present invention, and are not intended to limit the scope of the present invention. Any modifications or equivalent arrangements which may be readily devised by those skilled in the art are intended to be included within the scope of this invention as defined by the appended claims.

Claims

1. Ethernet transmission circuitry, characterized in that said Ethernet transmission circuitry comprises:

four sets of sub-circuits, each set of sub-circuits comprising:

a first capacitor coupled to a first input terminal of the sub-circuit;

a second capacitor coupled to a second input terminal of the sub-circuit; and

an ethernet transformer comprising a first coil, a second coil, and a magnetic core, the first coil and the second coil wound around the magnetic core, and wherein:

the first coil comprises a first input contact, a first output contact and a first center tap, wherein the first input contact is coupled to the first capacitor, the first center tap is coupled to a first output end of the sub-circuit, and the first output contact is coupled to ground; and is

The second coil includes a second input contact coupled to the second capacitor, a second output contact coupled to a second output of the sub-circuit, and a second center tap coupled to ground.

2. The ethernet transmission circuit according to claim 1, wherein in each of said sets of sub-circuits, said first center tap divides said first coil into a first left half coil and a first right half coil, said second center tap divides said second coil into a second left half coil and a second right half coil, said first left half coil is wound around said magnetic core in a direction opposite to said direction in which said first right half coil is wound around said magnetic core, and said second left half coil is wound around said magnetic core in a direction identical to said direction in which said second right half coil is wound around said magnetic core.

3. An ethernet transmission circuit according to claim 2, wherein said first left half-coil and said second left half-coil are wound around said core in opposite directions and of equal length.

4. An ethernet transmission circuit according to claim 1, wherein said ethernet transformer is configured to perform common-mode filtering for signals input from said first input terminal and said second input terminal.

5. The Ethernet transmission circuit of claim 1, wherein the Ethernet transformer is configured to provide a ground reference to avoid level shifting of the signals output by the first output terminal and the second output terminal.

6. An ethernet transmission circuit according to claim 1, wherein said first capacitor and said second capacitor are configured to couple signals input from said first input terminal and said second input terminal.