Vehicle-mounted Ethernet optimization circuit

Abstract

The utility model discloses a vehicle-mounted Ethernet optimization circuit, which comprises a transceiving unit, a protection unit, a filtering unit and a connection noise reduction unit, the transmitting-receiving unit and the filtering unit are connected with the conduction protection unit, the filtering unit and the connection noise reduction unit are conducted, the transmitting-receiving unit can protect the protection unit, the protection unit can protect a circuit, the filtering unit can suppress interference signals in the circuit, and the connection noise reduction unit can be in circuit connection and perform noise reduction. The beneficial effects of the utility model are that the ESD protection of the whole board can be realized, the noise and interference can be reduced, the signal integrity can be improved, the resistance-capacitance devices can be reduced, the cost can be reduced, and the test consistency of the BCI and the PMA can be improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of vehicle-mounted network technology, especially a vehicle-mounted Ethernet optimization circuit. BACKGROUND

[0002] Vehicle networks are rapidly evolving due to the rapid development of autonomous driving and connectivity technologies, driving the automotive industry forward. More functionality is needed to improve efficiency, safety, and driving experience. Therefore, the requirements for data bandwidth and the number of cables are increasingly high, and factors such as complexity, flexibility, and cost-effectiveness also become more challenging.

[0003] To achieve autonomous driving, a variety of technologies must be well integrated into the vehicle. This includes long-range radar, short / medium-range millimeter wave radar, lidar, cameras, ultrasonic sensors, and GPS, all of which operate at different data rates and communication protocols. Therefore, these decentralized networks are increasingly evolving into centralized network architectures.

[0004] These new features and applications all require reliance on expensive and complex wiring and electronic devices that require large bandwidth. This will be a key factor in increasing the price and weight of the car. To solve this problem, the newly developed BroadR- The 1000Mbit / s Automotive Ethernet specification attempts to optimize in-vehicle wiring, operating at 1000Mbit / s over a single unshielded twisted copper wire.

[0005] The BroadR-Reach 1000Mbit / s Automotive Ethernet standard aims to solve this problem - by allowing multiple vehicle systems to access information simultaneously through unshielded single twisted pair cables, reducing connection costs and wiring weight. A twisted pair cable is a type of electrical cable consisting of two insulated wires twisted together. It is a common transmission medium used in telecommunications, computer networks, and other applications. The two wires of a twisted pair are usually made of copper and are wrapped in an insulating layer. The two wires are twisted together to reduce external electromagnetic interference.

[0006] However, the existing technology has the following defects, (1) no whole board ESD protection; (2) cannot pass BCI and PMA consistency test; (3) poor signal integrity. SUMMARY

[0007] This section aims to outline some aspects of the embodiments of the present application and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract of the specification and the utility model name to avoid obscuring the purpose of this section, the abstract of the specification and the utility model name. Such simplifications or omissions cannot be used to limit the scope of the present application.

[0008] In view of the above or the problems existing in the prior art, the utility model provides.

[0009] Therefore, the utility model discloses a vehicle-mounted ethernet optimization circuit which can reduce noise and interference, improve signal integrity, reduce the cost of resistance-capacitance devices, protect the whole board ESD, and improve the consistency of BCI and PMA.

[0010] To solve the above technical problems, the utility model provides the following technical scheme: a vehicle-mounted ethernet optimization circuit, which comprises a transceiving unit, a protection unit, a filtering unit and a connection noise reduction unit.

[0011] As a preferred scheme of the utility model vehicle-mounted ethernet optimization circuit, the protection unit comprises an ESD protection device, the ESD protection device is connected with the positive and negative poles of the transceiving unit, and the ESD protection device is in conduction with the ground end.

[0012] As a preferred scheme of the utility model vehicle-mounted ethernet optimization circuit, the ESD protection device is used to protect the ethernet bus from damage by ESD and other transient voltages.

[0013] As a preferred scheme of the utility model vehicle-mounted ethernet optimization circuit, the filtering unit comprises a common-mode choke, the common-mode choke is respectively connected with the positive and negative poles of the transceiving unit and the positive and negative poles of the ETNB circuit, and the common-mode choke can effectively inhibit the propagation of common-mode interference signals.

[0014] As a preferred scheme of the utility model vehicle-mounted ethernet optimization circuit, the positive pole of the ETNB circuit is connected with a first capacitor, and the negative pole of the circuit is connected with a second capacitor; the specifications of the first capacitor and the second capacitor are 10nf and 50v.

[0015] As a preferred scheme of the utility model vehicle-mounted ethernet optimization circuit, the positive and negative poles of the ETNB circuit are connected with a first resistor and a second resistor, the first resistor and the second resistor are connected in circuit, the first resistor and the second resistor are 499Ω, and the precision is 1%.

[0016] As a preferred scheme of the utility model vehicle-mounted ethernet optimization circuit, the first resistor is connected with a third resistor, the third resistor is connected with a third capacitor and a ground end through a circuit, and the third capacitor is in circuit conduction with the first resistor and the second resistor.

[0017] As a preferred scheme of the utility model vehicle-mounted Ethernet optimization circuit, wherein: the third resistance is 100kΩ, and the precision is 5%; the third capacitor specification is 4.7nf, 100v.

[0018] As a preferred scheme of the utility model vehicle-mounted Ethernet optimization circuit, wherein: the connection noise reduction unit includes a connector, and the connector is connected with the filter unit and the filter circuit at two ends respectively.

[0019] As a preferred scheme of the utility model vehicle-mounted Ethernet optimization circuit, wherein: the filter circuit includes a fourth resistance and a fourth capacitor in parallel, the fourth resistance and the fourth capacitor are connected with the ground end through a circuit, the fourth resistance is 1MΩ, the precision is 1%, the fourth capacitor is 100nf, 50v.

[0020] The utility model has the advantages that the utility model can protect the whole board ESD, reduces noise and interference, improves signal integrity, can reduce the cost of resistance and capacitance devices, and can improve the test consistency of BCI and PMA. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical scheme of the embodiment of the utility model, the drawings needed in the embodiment description will be briefly introduced, and obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained without creative labor under the premise of the drawings.

[0022] Figure 1 It is the circuit schematic diagram of vehicle-mounted Ethernet optimization circuit.

[0023] Figure 2 It is 1000M Base-T1 interface circuit. DETAILED DESCRIPTION

[0024] In order to make the above purpose, features and advantages of the utility model more apparent and easy to understand, the specific implementation of the utility model will be described in detail in the following with the drawings of the specification.

[0025] In the following description, many specific details are set forth in order to provide a thorough understanding of the utility model, but the utility model can also be implemented in other ways different from the description, and those skilled in the art can make similar generalization without departing from the connotation of the utility model, therefore, the utility model is not limited by the specific embodiments disclosed below.

[0026] Secondly, the "one embodiment" or "embodiment" referred to herein is intended to mean a specific feature, structure, characteristic, or combination of features and characteristics described herein that is included in at least one implementation of the present application. The various appearances of "in one embodiment" or "in an embodiment" in the specification are not necessarily all referring to the same embodiment.

[0027] Embodiment 1

[0028] Referring to Figure 1 For the first embodiment of the present application, the embodiment provides a vehicle-mounted Ethernet optimization circuit, which comprises a transceiver unit 1, a protection unit 2, a filter unit 3, and a connection noise reduction unit 4; the transceiver unit 1 is connected in circuit with the protection unit 2 and the filter unit 3, and the filter unit 3 is connected in circuit with the connection noise reduction unit 4.

[0029] Specifically, it comprises a transceiver unit 1, a protection unit 2, a filter unit 3, and a connection noise reduction unit 4; the protection unit 2 is connected between the transceiver unit 1 and the filter unit 3, and the filter unit 3 is connected with the connection noise reduction unit 4; the transceiver unit 1 can protect the protection unit 2, the protection unit 2 can protect the circuit, the filter unit 3 can suppress the interference signal in the circuit, and the connection noise reduction unit 4 can be connected in circuit and reduce noise.

[0030] Preferably, the transceiver unit 1 comprises a physical layer interface PHY and some basic filter elements and on-chip ESD protection.

[0031] Further, the protection unit 2 comprises an ESD protection device 21, which is connected with the positive and negative poles of the transceiver unit 1, and the ESD protection device 21 is connected with the ground.

[0032] Further, the ESD protection device 21 is used to protect the Ethernet bus from ESD and other transient voltages.

[0033] Preferably, the ESD current is clamped to GND, so it will not affect the PCB, Ethernet PHY or other elements. According to the requirements of 1000MBase-T1 specification, when the ESD protection device with a trigger voltage exceeding 100V is placed on the connector in front of the common-mode choke 31, it can play a more significant protective role.

[0034] Further, the filter unit 3 comprises a common-mode choke 31, which is respectively connected with the positive and negative poles of the transceiver unit 1 and the positive and negative poles of the ETNB circuit, and the common-mode choke 31 can effectively suppress the propagation of common-mode interference signals.

[0035] Preferably, by setting the common-mode choke 31, the unnecessary common mode can be reduced, thereby reducing EMI.

[0036] Further, the ETNB positive electrode circuit is connected with the first capacitor 32, and the negative electrode circuit is connected with the second capacitor 33; the specifications of the first capacitor 32 and the second capacitor 33 are 10nf, 50v.

[0037] Further, the ETNB positive electrode circuit is connected with the first resistor 34 and the second resistor 35, and the first resistor 34 and the second resistor 35 are connected in circuit; the first resistor 34 and the second resistor 35 are 499Ω, and the accuracy is 1%.

[0038] Further, the first resistor 34 is connected with the third resistor 36, the third resistor 36 is connected with the third capacitor 37 and the ground terminal through circuit, and the third capacitor 37 is connected with the first resistor 34 and the second resistor 35 in circuit.

[0039] Further, the third resistor 36 is 100kΩ, and the accuracy is 5%; the specification of the third capacitor 37 is 4.7nf, 100v.

[0040] Preferably, the specification of the third capacitor 37 is adjusted from 100nf to 4.7nf, 100v, and the BCI has better performance.

[0041] Further, the connection of the noise reduction unit 4 includes the connector 41, and the two ends of the connector 41 are respectively connected with the filter unit 3 and the filter circuit.

[0042] Further, the filter circuit includes the fourth resistor 42 and the fourth capacitor 43 connected in parallel, and the fourth resistor 42 and the fourth capacitor 43 are connected with the ground terminal through circuit; the fourth resistor 42 is 1MΩ, and the accuracy is 1%; the fourth capacitor 43 is 100nf, 50v.

[0043] Preferably, the fourth resistor 42 and the fourth capacitor 43 are added at the end of the connector 41, which can better filter the noise.

[0044] It should be noted that the basic architecture of the vehicle Ethernet is still MAC + PHY chip + transmission link, and the most significant feature of 1000Base-T1 is to use a single pair of differential lines to realize data transmission, which reduces the cost and weight of the wiring harness in terms of cost, uses PAM3 signaling, and uses the amplitude of the signal to encode data. PAM3 uses three different levels. The receiver sets high and low thresholds to determine the level. Any sample higher than the high level is +1, lower than the low level is -1, and between the two levels is 0. Two ternary symbols form a code group. When a code group represents data, it represents 3-bit data. The specification defines how these code groups are mapped to 3-bit data, and uses rate conversion and changing encoding methods to convert MAC layer 1000Mbps data into a 750Mbps baud rate signal on twisted pair, so that the vehicle Ethernet can achieve high data rate with lower wiring cost. Lower signal bandwidth can improve return loss, reduce crosstalk, and ensure that the vehicle Ethernet can meet the requirements of automotive electromagnetic radiation standards. But this also has higher requirements for external line design, so there is more room for optimization of the line.

[0045] 1000Base-T1 line is defined by the standard, and the scheme is adjusted and optimized from the actual application. The main purpose is to improve return loss, reduce crosstalk, and ensure that the vehicle Ethernet can meet the requirements of automotive electromagnetic radiation standards, and ensure that PMA consistency can pass.

[0046] Reference Figure 2 Compared with the interface line of 1000Base-T1, the scheme can achieve better signal integrity, and the BCI / PMA test performance is better, and the filtering part is more simplified, and the power supply noise is reduced.

[0047] The utility model discloses a whole board ESD protection, reduces noise and interference, improves the integrity of signal, can reduce the resistance and capacitance device and reduce the cost, can promote the test consistency of BCI and PMA.

[0048] It is important to note that the construction and arrangements of the application shown in the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications can be made to the embodiments without departing from the novel teachings and advantages of the subject matter described herein. For example, elements described as integrated in a single unit can be separated, elements described as separate can be integrated, and the position, number, shape, and arrangements of elements can be varied. Accordingly, all such modifications are intended to be included within the scope of the present inventive subject matter. The order or sequence of any process or method steps can be varied or re-sequenced without departing from the general nature of the claims. Any "means plus function" clauses are intended to cover the structures described herein as performing the recited functionality and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes, and omissions can be made in the design, operating conditions, and arrangement of the exemplary embodiments without departing from the scope of the present inventive subject matter. Accordingly, the present inventive subject matter is not limited to the particular embodiments described and illustrated herein, but extends to equivalents of which the foregoing describes are intended to cover.

[0049] Furthermore, in order to provide a concise description of the exemplary embodiments, not all features of an actual implementation can be described (i.e., those pertaining to the

[0050] It is understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions can be made. Such development efforts can inevitably lead to a number of substitutions, modifications, changes, and omissions of parts illustrated as having a specific configuration. Such are the natural consequences of research and development efforts, and

[0051] It should be noted that the above examples are only used to illustrate the technical solutions of the present application but not limit the present application, and although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and all should be included in the scope of the claims of the present application.

Claims

1. An in-vehicle Ethernet optimization circuit, comprising: It includes transceiver unit (1), protection unit (2), filter unit (3), and connecting noise reduction unit (4); the transceiver unit (1) and filter unit (3) are connected with the on-off protection unit (2), the filter unit (3) is connected with the on-off noise reduction unit (4), the transceiver unit (1) can protect the protection unit (2), the protection unit (2) can protect the circuit, the filter unit (3) can inhibit the interference signal in the circuit, and the connecting noise reduction unit (4) can be connected and reduced in the circuit.

2. The on-board Ethernet optimization circuit of claim 1, wherein: The protection unit (2) includes an ESD protection device (21), the ESD protection device (21) is connected with the positive and negative electrodes of the transceiver unit (1), and the ESD protection device (21) is connected with the ground end.

3. The on-board Ethernet optimization circuit of claim 2, wherein: The ESD protection device (21) is used for protecting the Ethernet bus from ESD and other transient voltages.

4. The on-board Ethernet optimization circuit of claim 1, wherein: The filter unit (3) includes a common mode choke (31), the common mode choke (31) is respectively connected with the positive and negative electrodes of the transceiver unit (1) and the positive and negative electrodes of the ETNB circuit, and the common mode choke (31) can effectively inhibit the propagation of common mode interference signals.

5. The on-board Ethernet optimization circuit of claim 4, wherein: The positive electrode of the ETNB circuit is connected with a first capacitor (32), and the negative electrode circuit is connected with a second capacitor (33); the specifications of the first capacitor (32) and the second capacitor (33) are 10nf, 50v.

6. The on-board Ethernet optimization circuit of claim 5, wherein: The positive and negative electrodes of the ETNB circuit are connected with a first resistor (34) and a second resistor (35), the first resistor (34) and the second resistor (35) are connected in circuit, the first resistor (34) and the second resistor (35) are 499Ω, and the accuracy is 1%.

7. The on-board Ethernet optimization circuit of claim 6, wherein: The first resistor (34) is connected with a third resistor (36), the third resistor (36) is connected with a third capacitor (37) and a ground end through a circuit, and the third capacitor (37) is connected with the first resistor (34) and the second resistor (35) in circuit.

8. The on-board Ethernet optimization circuit of claim 7, wherein: The third resistor (36) is 100kΩ, and the accuracy is 5%; the specification of the third capacitor (37) is 4.7nf, 100v.

9. The on-board Ethernet optimization circuit of claim 1, wherein: The connecting noise reduction unit (4) includes a connector (41), the connector (41) is respectively connected with the filter unit (3) and the filter circuit at both ends.

10. The on-board Ethernet optimization circuit of claim 9, wherein: The filter circuit includes a fourth resistor (42) and a fourth capacitor (43) connected in parallel, the fourth resistor (42) and the fourth capacitor (43) are connected with the ground end through a circuit, the fourth resistor (42) is 1MΩ, the accuracy is 1%, the fourth capacitor (43) is 100nf, and the voltage is 50v.

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