A network switching circuit

Abstract

The utility model discloses a network switching circuit, include: power module, control chip, switching module, transformer module, protection module, first interface module and second interface module, the power module is connected control chip, control chip is connected transformer module through switching module, switching module connects second interface module, transformer module is connected protection module and first interface module respectively, this circuit is used for the scene (such as network debugging, main spare switching, security isolation) that needs frequently or quick change network environment, thoroughly eliminated because repeatedly plug and unplug network cable leads network interface (RJ45), crystal head and cable's mechanical wear and tear and physical damage, has prolonged the service life of equipment interface, has guaranteed the stability of long -term connection.

Description

Technical Field

[0001] This utility model relates to the field of electronic circuit technology, specifically to a network switching circuit. Background Technology

[0002] In today's information-driven society, stable network connectivity is an indispensable foundation for personal computing, enterprise operations, and industrial control. As network application scenarios become increasingly complex, a network device often needs to connect to multiple different physical networks, such as a local area network (LAN) for internal data transmission and a public network for internet access, or switch between primary and backup networks to ensure business continuity.

[0003] In traditional technical solutions, switching devices between different networks typically relies on manually plugging and unplugging network cables. When a user needs to change from one network environment to another, the network cable must be unplugged from the current network's interface and then plugged into the target network's interface. This physical operation method has several inherent drawbacks:

[0004] Frequent plugging and unplugging operations are cumbersome and time-consuming, especially in scenarios requiring rapid response or remote management. Manual on-site operation can cause significant delays and cannot meet the requirements of modern business for efficiency and real-time performance.

[0005] Network interfaces (RJ45) and their connectors have a specified physical mating life. Repeated mechanical handling accelerates wear and oxidation of the interface and cable connectors, leading to poor contact, which in turn causes network instability, speed reduction, or even interruption, increasing maintenance costs and failure risks. Utility Model Content

[0006] To overcome the above-mentioned technical defects, this utility model provides a network switching circuit.

[0007] To solve the above problems, this utility model is implemented according to the following technical solution:

[0008] The network switching circuit of this utility model includes: a power supply module, a control chip, a switching module, a transformer module, a protection module, a first interface module, and a second interface module; the power supply module is connected to the control chip; the control chip is connected to the transformer module through the switching module; the switching module is connected to the second interface module; the transformer module is connected to both the protection module and the first interface module.

[0009] Preferably, the switching module includes: an analog switch chip, a first resistor, a second resistor, and a first capacitor; the DA pin of the analog switch chip is connected to the MDI1+ pin of the control chip; the DB pin of the analog switch chip is connected to the MDI1- pin of the control chip; the DD pin of the analog switch chip is connected to the MDI0- pin of the control chip; the DC pin of the analog switch chip is connected to the MDI0+ pin of the control chip; the VCC pin of the analog switch chip is connected to one end of the first resistor and one end of the first capacitor, the other end of the first resistor is connected to the power supply module, and the other end of the first capacitor is grounded; the EN pin of the analog switch chip is grounded through the second resistor.

[0010] Preferably, the transformer module includes: a first transformer circuit and a second transformer circuit; the first transformer circuit is connected to the second transformer circuit via a switching module.

[0011] Preferably, the protection module includes a first TVS diode and a second TVS diode, wherein the first TVS diode is connected to the first transformer circuit, and the second TVS diode is connected to the second transformer circuit.

[0012] Preferably, the first transformer circuit includes: a first network filter, a second capacitor, a third capacitor, a fourth capacitor, a third resistor, a fourth resistor, a first common-mode filter, a first transformer, a second common-mode filter, and a second transformer; the TDP pin of the first network filter is connected to the S1C pin of the analog switch chip and the fourth pin of the first common-mode filter, respectively; the TDN pin of the first network filter is connected to the S1D pin of the analog switch chip and the first pin of the first common-mode filter, respectively; the RDP pin of the first network filter is connected to the S1A pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively; the RDN pin of the first network filter is connected to the S1B pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively; the TDC pin of the first network filter is connected to the third pin of the first transformer and one end of the second capacitor, and the other end of the second capacitor is grounded; the RDC pin of the first network filter is connected to the third pin of the second transformer and one end of the third capacitor, and the other end of the third capacitor is grounded; the TXP pin of the first network filter is connected to the first pin of the first TVS diode, and the second pin of the first TVS diode is connected to the first transformer... The first pin of the transformer; the TXC pin of the first network filter is connected to one end of the third resistor and the sixth pin of the first transformer, and the other end of the third resistor is grounded through the fourth capacitor; the TXN pin of the first network filter is connected to the third pin of the first TVS diode, and the fourth pin of the first TVS diode is connected to the second pin of the first transformer; the RXP pin of the first network filter is connected to the fifth pin of the first TVS diode, and the sixth pin of the first TVS diode is connected to the first pin of the second transformer; the RXC pin of the first network filter is connected to one end of the fourth resistor and the sixth pin of the second transformer, and the other end of the fourth resistor is grounded through the fourth capacitor; the RXN pin of the first network filter is connected to the seventh pin of the first TVS diode, and the eighth pin of the first TVS diode is connected to the second pin of the second transformer; the third pin of the first common-mode filter is connected to the fifth pin of the first transformer, and the second pin of the first common-mode filter is connected to the fourth pin of the first transformer; the third pin of the second common-mode filter is connected to the fifth pin of the second transformer, and the second pin of the second common-mode filter is connected to the fourth pin of the second transformer.

[0013] Preferably, the second transformer circuit includes: a second network filter, a fifth capacitor, a sixth capacitor, a seventh capacitor, a fifth resistor, a sixth resistor, a third common-mode filter, a third transformer, a fourth common-mode filter, and a fourth transformer; the TDP pin of the second network filter is connected to the S2C pin of the analog switch chip and the fourth pin of the third common-mode filter, respectively; the TDN pin of the second network filter is connected to the S2D pin of the analog switch chip and the first pin of the third common-mode filter, respectively; the RDP pin of the second network filter is connected to the S2A pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively; the RDN pin of the second network filter is connected to the S2B pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively; the TDC pin of the second network filter is connected to the third pin of the third transformer and one end of the fifth capacitor, with the other end of the fifth capacitor grounded; the RDC pin of the second network filter is connected to the third pin of the fourth transformer and one end of the sixth capacitor, with the other end of the sixth capacitor grounded; the TXP pin of the second network filter is connected to the first pin of the second TVS diode, and the second pin of the second TVS diode is connected to the third transformer... The first pin of the transformer; the TXC pin of the second network filter is connected to one end of the fifth resistor and the sixth pin of the third transformer, respectively, and the other end of the fifth resistor is grounded through the seventh capacitor; the TXN pin of the second network filter is connected to the third pin of the second TVS diode, and the fourth pin of the second TVS diode is connected to the second pin of the third transformer; the RXP pin of the second network filter is connected to the fifth pin of the second TVS diode, and the sixth pin of the second TVS diode is connected to the first pin of the fourth transformer; the RXC pin of the second network filter is connected to one end of the sixth resistor and the sixth pin of the third transformer, respectively, and the other end of the sixth resistor is grounded through the seventh capacitor; the RXN pin of the second network filter is connected to the seventh pin of the second TVS diode, and the eighth pin of the second TVS diode is connected to the second pin of the fourth transformer; the third pin of the third common-mode filter is connected to the fifth pin of the third transformer, and the second pin of the third common-mode filter is connected to the fourth pin of the third transformer; the third pin of the fourth common-mode filter is connected to the fifth pin of the fourth transformer, and the second pin of the fourth common-mode filter is connected to the fourth pin of the fourth transformer.

[0014] Preferably, the power module includes: a power input circuit, a first power conversion circuit, and a second power conversion circuit; the power input circuit is connected to the second power conversion circuit through the first power conversion circuit.

[0015] Preferably, it further includes: an indicator light module, the indicator light module including a first indicator light circuit and a second indicator light circuit; the first indicator light circuit is respectively connected to the control chip and the second power conversion circuit; the second indicator light circuit is connected to the control chip and the second power conversion circuit.

[0016] Preferably, the first indicator light circuit includes: a first surface-mount transistor, a second surface-mount transistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a first electrostatic diode, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, an eighth capacitor, a first transistor, a second transistor, and a second electrostatic diode; one end of the eighth resistor is connected to the LED0 / PHYAD0 pin of the control chip; one end of the ninth resistor is connected to the LED0 / PHYAD0 pin of the control chip, and the other end of the ninth resistor is grounded; the base of the first surface-mount transistor is connected to the LED0 / PHYAD0 pin of the control chip, the collector of the first surface-mount transistor is connected to the base of the second surface-mount transistor and one end of the tenth resistor, the other end of the tenth resistor is connected to one end of the eleventh resistor, and the emitter of the first surface-mount transistor... The first transistor is grounded at one end; the other end of the eleventh resistor is grounded through the first electrostatic diode, and the other end of the eleventh resistor is connected to the collector of the second surface-mount transistor, and the emitter of the second surface-mount transistor is grounded; one end of the twelfth resistor is connected to the collector of the second surface-mount transistor, and the other end of the twelfth resistor is connected to one end of the thirteenth resistor; the base of the first transistor is connected to the other end of the thirteenth resistor, and the emitter of the first transistor is connected to one end of the eighth capacitor and one end of the fourteenth resistor, respectively, and the collector of the first transistor and the other end of the eighth capacitor are grounded; the base of the second transistor is connected to the other end of the fourteenth resistor, and the collector of the second transistor is connected to one end of the fifteenth resistor; one end of the second electrostatic diode is connected to the other end of the fifteenth resistor, and the other end of the second electrostatic diode is grounded.

[0017] Preferably, the first indicator light circuit includes: a third surface-mount transistor, a fourth surface-mount transistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a third electrostatic diode, a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a ninth capacitor, a third transistor, a fourth transistor, and a fourth electrostatic diode; one end of the sixteenth resistor is connected to the LED1 / PHYAD1 pin of the control chip, and the other end of the sixteenth resistor is connected to the other end of the sixteenth resistor; one end of the seventeenth resistor is connected to the LED1 / PHYAD1 pin of the control chip, and the other end of the seventeenth resistor is grounded; the base of the third surface-mount transistor is connected to the LED1 / PHYAD1 pin of the control chip, the collector of the third surface-mount transistor is connected to the base of the fourth surface-mount transistor and one end of the eighteenth resistor, and the other end of the eighteenth resistor is connected to the nineteenth resistor. At one end, the emitter of the fourth surface-mount transistor is grounded; the other end of the nineteenth resistor is grounded through the second electrostatic diode, and the other end of the nineteenth resistor is connected to the collector of the fourth surface-mount transistor, and the emitter of the fourth surface-mount transistor is grounded; one end of the twentieth resistor is connected to the collector of the second surface-mount transistor, and the other end of the twentieth resistor is connected to one end of the twentieth eleventh resistor; the base of the third transistor is connected to the other end of the twentieth eleventh resistor, and the emitter of the third transistor is connected to one end of the ninth capacitor and one end of the twentieth twentieth resistor, respectively, and the collector of the third transistor and the other end of the ninth capacitor are grounded; the base of the fourth transistor is connected to the other end of the twentieth twentieth resistor, and the collector of the fourth transistor is connected to one end of the twentieth thirteenth resistor; one end of the fourth electrostatic diode is connected to the other end of the twentieth thirteenth resistor, and the other end of the fourth electrostatic diode is grounded.

[0018] Compared with the prior art, the beneficial effects of this utility model are:

[0019] By controlling the switching module with a chip, users can quickly and automatically switch between different networks (such as the networks connected to the first and second interfaces) without physically plugging and unplugging network cables, based on software commands or preset conditions. This greatly improves operational efficiency and is particularly suitable for scenarios requiring frequent or rapid changes to the network environment (such as network debugging, primary / backup switching, and security isolation). It completely eliminates mechanical wear and physical damage to network interfaces (RJ45), connectors, and cables caused by repeated plugging and unplugging, extending the lifespan of the device interfaces and ensuring long-term connection stability. Replacing mechanical plugging and unplugging with electronic switching avoids problems such as poor contact and port oxidation, ensuring the continuity and quality of signal transmission and reducing network failures caused by connection issues. Attached Figure Description

[0020] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings, wherein:

[0021] Figure 1 This is the circuit schematic diagram of the power module of this utility model.

[0022] Figure 2 This invention relates to the principle of the network switching circuit. Figure 1 .

[0023] Figure 3 This invention relates to the principle of the network switching circuit. Figure 2 .

[0024] Figure 4 This is the circuit diagram of the indicator light module of this utility model.

[0025] In the diagram: 1-Power input circuit; 2-First power conversion circuit; 3-Second power conversion circuit; 4-Control chip; 5-Switching module; 6-Transformer module; 61-First transformer circuit; 62-Second transformer circuit; 7-Protection module; 8-First interface module; 9-Second interface module; 10-Indicator light module. Detailed Implementation

[0026] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0027] like Figures 1-4 As shown, this utility model discloses a preferred structure of a network switching circuit.

[0028] The network switching circuit of this utility model includes: a power supply module, a control chip 4, a switching module 5, a transformer module 6, a protection module 7, a first interface module 8, and a second interface module 9; the power supply module is connected to the control chip 4; the control chip 4 is connected to the transformer module 6 through the switching module 5; the switching module 5 is connected to the second interface module 9; the transformer module 6 is connected to the protection module 7 and the first interface module 8 respectively.

[0029] Specifically, the control chip 4 intelligently controls the switching module 5 to achieve signal path selection between network interfaces. The power module provides a stable operating voltage to the control chip. The control chip sends control signals to the switching module according to external instructions or internal logic. The switching module 5 is driven by the control chip. The transformer module 6 realizes electrical isolation and signal coupling between the front and rear stage circuits and matches the impedance of the network signals. The protection module 7 is used to protect against external electrical interference from the first interface and ensure the safety of the internal circuit. The first interface module is a standard network physical interface (such as RJ45) used to connect different external network cables. When a network switch is required, the control chip commands the switching module to change the path. The network data stream can be selected to enter the transformer module directly from the second interface via the switching module, or sent from the control chip via the switching module to the transformer module. Ultimately, after coupling and isolation by the transformer module, it is output to the target device by the protection module and the first interface module.

[0030] Preferably, the switching module 5 includes: an analog switch chip, a first resistor, a second resistor, and a first capacitor; the DA pin of the analog switch chip is connected to the MDI1+ pin of the control chip; the DB pin of the analog switch chip is connected to the MDI1- pin of the control chip; the DD pin of the analog switch chip is connected to the MDI0- pin of the control chip; the DC pin of the analog switch chip is connected to the MDI0+ pin of the control chip; the VCC pin of the analog switch chip is connected to one end of the first resistor and one end of the first capacitor, the other end of the first resistor is connected to the power supply module, and the other end of the first capacitor is grounded; the EN pin of the analog switch chip is grounded through the second resistor.

[0031] Specifically, the analog switch chip, acting as the core selector, internally contains multiple electronic switches. The DA, DB, DC, and DD data pins of the analog switch chip are connected to the four differential signal pins (MDI1+, MDI1-, MDI0-, MDI0+) of the control chip, thus establishing two complete pairs of transmit and receive differential signal channels. The VCC pin of the analog switch chip is connected to the power supply via a pull-up resistor (first resistor) and simultaneously connected to ground via a decoupling capacitor (first capacitor) to ensure power stability and noise filtering. Its EN (enable) pin is grounded via a pull-down resistor (second resistor), and the analog switch chip is in enabled operating mode by default, ensuring circuit stability and controllability. The control chip dynamically selects the connection path of its data pins by controlling the state of the internal switches of the analog switch chip. When network switching is required, the control chip can change the configuration of the analog switch, thereby conducting network signals from itself (MDIx pin) or from the second interface module (through the other channel of the analog switch) to the transformer module, ultimately achieving electronic switching of the signal path.

[0032] Preferably, the transformer module includes: a first transformer circuit 61 and a second transformer circuit 62; the first transformer circuit 61 is connected to the second transformer circuit 62 through a switching module 5.

[0033] Specifically, the transformer module consists of a first transformer circuit 61 and a second transformer circuit 62. They are physically independent but electrically connected through a switching module 5. Each transformer circuit includes a network transformer and necessary peripheral components, respectively performing coupling, electrical isolation, and impedance matching functions for one network signal. The first and second transformer circuits are not directly connected but are connected through the switching module. This switching module determines whether to connect the signal paths on the secondary side (or designated side) of the two transformer circuits based on control signals. After entering through the switching module, the network signal may flow through either the first or second transformer circuit for processing.

[0034] It can achieve two operating modes: Independent operating mode: When the switching module is disconnected, the two transformer circuits operate independently, processing different signal paths, achieving complete physical and electrical isolation of the signals. Cascaded operating mode: When the switching module is closed, the signal processed by the first transformer circuit can be coupled to the second transformer circuit, realizing series transmission of signals or merging of different signal paths, providing greater connection flexibility for the circuit.

[0035] Preferably, the protection module 7 includes a first TVS diode and a second TVS diode, wherein the first TVS diode is connected to the first transformer circuit 61 and the second TVS diode is connected to the second transformer circuit 62.

[0036] Preferably, the first transformer circuit 61 includes: a first network filter, a second capacitor, a third capacitor, a fourth capacitor, a third resistor, a fourth resistor, a first common-mode filter, a first transformer, a second common-mode filter, and a second transformer; the TDP pin of the first network filter is connected to the S1C pin of the analog switch chip and the fourth pin of the first common-mode filter; the TDN pin of the first network filter is connected to the S1D pin of the analog switch chip and the first pin of the first common-mode filter; the RDP pin of the first network filter is connected to the S1A pin of the analog switch chip and the fourth pin of the second common-mode filter; the RDN pin of the first network filter is connected to the S1B pin of the analog switch chip and the fourth pin of the second common-mode filter; the TDC pin of the first network filter is connected to the third pin of the first transformer and one end of the second capacitor, and the other end of the second capacitor is grounded; the RDC pin of the first network filter is connected to the third pin of the second transformer and one end of the third capacitor, and the other end of the third capacitor is grounded; the TXP pin of the first network filter is connected to the first pin of the first TVS diode, and the second pin of the first TVS diode is connected to the first... The transformer has a first pin; the TXC pin of the first network filter is connected to one end of the third resistor and the sixth pin of the first transformer, and the other end of the third resistor is grounded through the fourth capacitor; the TXN pin of the first network filter is connected to the third pin of the first TVS diode, and the fourth pin of the first TVS diode is connected to the second pin of the first transformer; the RXP pin of the first network filter is connected to the fifth pin of the first TVS diode, and the sixth pin of the first TVS diode is connected to the first pin of the second transformer; the RXC pin of the first network filter is connected to one end of the fourth resistor and the sixth pin of the second transformer, and the other end of the fourth resistor is grounded through the fourth capacitor; the RXN pin of the first network filter is connected to the seventh pin of the first TVS diode, and the eighth pin of the first TVS diode is connected to the second pin of the second transformer; the third pin of the first common-mode filter is connected to the fifth pin of the first transformer, and the second pin of the first common-mode filter is connected to the fourth pin of the first transformer; the third pin of the second common-mode filter is connected to the fifth pin of the second transformer, and the second pin of the second common-mode filter is connected to the fourth pin of the second transformer.

[0037] Specifically, the signal enters the TDP / TDN (transmit differential pair) and RDP / RDN (receive differential pair) pins of the first network filter from the analog switch chip. The first network filter is responsible for the initial waveform shaping and filtering of the network signal. The network signal then passes through the first and second common-mode filters, which strongly suppress common-mode noise in the transmit and receive paths, respectively. The first and second transformers are isolation components; they transmit signals through magnetic coupling, achieving complete electrical isolation between the front-end circuit and the back-end network interface, effectively blocking ground loops and high-voltage interference. The second and third capacitors provide a reference potential and decoupling for the transformer center tap. The third, fourth, and fourth resistors and capacitors constitute a bias circuit, providing a stable DC operating point for the transmit and receive channels. The first TVS diode provides efficient electrostatic discharge (ESD) and surge protection, clamping abnormal high voltage to a safe level. The transmit signal, after being conditioned by the network filter, is purified by the common-mode filter, then isolated and coupled out through the transformer; the receive signal follows the opposite path, first being isolated by the transformer, then processed by the common-mode filter and the network filter before being sent to the switching module.

[0038] Preferably, the second transformer circuit 62 includes: a second network filter, a fifth capacitor, a sixth capacitor, a seventh capacitor, a fifth resistor, a sixth resistor, a third common-mode filter, a third transformer, a fourth common-mode filter, and a fourth transformer; the TDP pin of the second network filter is connected to the S2C pin of the analog switch chip and the fourth pin of the third common-mode filter, respectively; the TDN pin of the second network filter is connected to the S2D pin of the analog switch chip and the first pin of the third common-mode filter, respectively; the RDP pin of the second network filter is connected to the S2A pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively; the RDN pin of the second network filter is connected to the S2B pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively; the TDC pin of the second network filter is connected to the third pin of the third transformer and one end of the fifth capacitor, and the other end of the fifth capacitor is grounded; the RDC pin of the second network filter is connected to the third pin of the fourth transformer and one end of the sixth capacitor, and the other end of the sixth capacitor is grounded; the TXP pin of the second network filter is connected to the first pin of the second TVS diode, and the second pin of the second TVS diode is connected to the third common-mode filter; The transformer has a first pin; the second network filter's TXC pin is connected to one end of the fifth resistor and the sixth pin of the third transformer, with the other end of the fifth resistor grounded through the seventh capacitor; the second network filter's TXN pin is connected to the third pin of the second TVS diode, and the fourth pin of the second TVS diode is connected to the second pin of the third transformer; the second network filter's RXP pin is connected to the fifth pin of the second TVS diode, and the sixth pin of the second TVS diode is connected to the first pin of the fourth transformer; the second network filter's RXC pin is connected to one end of the sixth resistor and the sixth pin of the third transformer, with the other end of the sixth resistor grounded through the seventh capacitor; the second network filter's RXN pin is connected to the seventh pin of the second TVS diode, and the eighth pin of the second TVS diode is connected to the second pin of the fourth transformer; the third pin of the third common-mode filter is connected to the fifth pin of the third transformer, and the second pin of the third common-mode filter is connected to the fourth pin of the third transformer; the third pin of the fourth common-mode filter is connected to the fifth pin of the fourth transformer, and the second pin of the fourth common-mode filter is connected to the fourth pin of the fourth transformer.

[0039] Preferably, the power module includes: a power input circuit 1, a first power conversion circuit 2, and a second power conversion circuit 3; the power input circuit 1 is connected to the second power conversion circuit 3 through the first power conversion circuit 2.

[0040] Preferably, it further includes: an indicator light module 10, the indicator light module 10 including a first indicator light circuit and a second indicator light circuit; the first indicator light circuit is respectively connected to the control chip and the second power conversion circuit; the second indicator light circuit is connected to the control chip and the second power conversion circuit.

[0041] Specifically, the indicator module consists of two independent units: a first indicator circuit and a second indicator circuit. Both indicator circuits are connected to a second power conversion circuit to obtain operating power and are also connected to a control chip to receive control signals from it. Based on the circuit's operating state (such as network connection status, data activity status, and whether a switch was successful), the control chip drives specific pins on the main control chip to control the on / off state, flashing, or color change of the first and second indicator circuits, thereby converting the internal state into a visible light signal.

[0042] Preferably, the first indicator light circuit includes: a first surface-mount transistor, a second surface-mount transistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a first electrostatic diode, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, an eighth capacitor, a first transistor, a second transistor, and a second electrostatic diode; one end of the eighth resistor is connected to the LED0 / PHYAD0 pin of the control chip; one end of the ninth resistor is connected to the LED0 / PHYAD0 pin of the control chip, and the other end of the ninth resistor is grounded; the base of the first surface-mount transistor is connected to the LED0 / PHYAD0 pin of the control chip, the collector of the first surface-mount transistor is connected to the base of the second surface-mount transistor and one end of the tenth resistor, the other end of the tenth resistor is connected to one end of the eleventh resistor, and the emitter of the first surface-mount transistor... The first transistor is grounded at one end; the other end of the eleventh resistor is grounded through the first electrostatic diode, and the other end of the eleventh resistor is connected to the collector of the second surface-mount transistor, and the emitter of the second surface-mount transistor is grounded; one end of the twelfth resistor is connected to the collector of the second surface-mount transistor, and the other end of the twelfth resistor is connected to one end of the thirteenth resistor; the base of the first transistor is connected to the other end of the thirteenth resistor, and the emitter of the first transistor is connected to one end of the eighth capacitor and one end of the fourteenth resistor, respectively, and the collector of the first transistor and the other end of the eighth capacitor are grounded; the base of the second transistor is connected to the other end of the fourteenth resistor, and the collector of the second transistor is connected to one end of the fifteenth resistor; one end of the second electrostatic diode is connected to the other end of the fifteenth resistor, and the other end of the second electrostatic diode is grounded.

[0043] Specifically, the LED0 / PHYAD0 pin of the control chip outputs a control signal. This pin is simultaneously connected to the eighth and ninth resistors (a pull-up / pull-down configuration) and the base of the first surface-mount transistor. When the control signal is high, the first surface-mount transistor conducts. The conduction of the first surface-mount transistor pulls down the base voltage of the second surface-mount transistor, causing it to conduct as well. The collector current path of the second surface-mount transistor passes through the eleventh resistor and the first ESD protection diode. The voltage change at the collector of the second surface-mount transistor is transmitted to the base of the first transistor through the twelfth and thirteenth resistors, controlling its conduction. After the first transistor conducts, it provides operating voltage and current to the fourteenth resistor connected to its emitter and the second transistor, etc. The second transistor, as the final output driver, has its collector current flowing through the fifteenth resistor and the second ESD diode, driving the actual indicator LED to light up. The control chip sends a high / low level signal → the first surface-mount transistor switches → the second surface-mount transistor switches → the first transistor switches → the second transistor switches → the indicator light turns on / off.

[0044] Preferably, the first indicator light circuit includes: a third surface-mount transistor, a fourth surface-mount transistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a third electrostatic diode, a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a ninth capacitor, a third transistor, a fourth transistor, and a fourth electrostatic diode; one end of the sixteenth resistor is connected to the LED1 / PHYAD1 pin of the control chip, and the other end of the sixteenth resistor is connected to the other end of the sixteenth resistor; one end of the seventeenth resistor is connected to the LED1 / PHYAD1 pin of the control chip, and the other end of the seventeenth resistor is grounded; the base of the third surface-mount transistor is connected to the LED1 / PHYAD1 pin of the control chip, the collector of the third surface-mount transistor is connected to the base of the fourth surface-mount transistor and one end of the eighteenth resistor, and the other end of the eighteenth resistor is connected to the nineteenth resistor. At one end, the emitter of the fourth surface-mount transistor is grounded; the other end of the nineteenth resistor is grounded through the second electrostatic diode, and the other end of the nineteenth resistor is connected to the collector of the fourth surface-mount transistor, and the emitter of the fourth surface-mount transistor is grounded; one end of the twentieth resistor is connected to the collector of the second surface-mount transistor, and the other end of the twentieth resistor is connected to one end of the twentieth eleventh resistor; the base of the third transistor is connected to the other end of the twentieth eleventh resistor, and the emitter of the third transistor is connected to one end of the ninth capacitor and one end of the twentieth twentieth resistor, respectively, and the collector of the third transistor and the other end of the ninth capacitor are grounded; the base of the fourth transistor is connected to the other end of the twentieth twentieth resistor, and the collector of the fourth transistor is connected to one end of the twentieth thirteenth resistor; one end of the fourth electrostatic diode is connected to the other end of the twentieth thirteenth resistor, and the other end of the fourth electrostatic diode is grounded.

[0045] Specifically, the LED1 / PHYAD1 pin of the control chip outputs a control signal. This pin is simultaneously connected to the sixteenth and seventeenth resistors (a pull-up / pull-down configuration) and the base of the first surface-mount transistor. When the control signal is high, the third surface-mount transistor conducts. The conduction of the third surface-mount transistor pulls down the base voltage of the fourth surface-mount transistor, causing it to conduct as well. The collector current path of the third surface-mount transistor passes through the nineteenth resistor and the third ESD protection diode. The voltage change at the collector of the fourth surface-mount transistor is transmitted to the base of the third transistor through the twentieth and twenty-first resistors, controlling its conduction. After the third transistor conducts, it provides operating voltage and current to the twenty-second resistor connected to its emitter and the fourth transistor, etc. The fourth transistor, as the final output driver, has its collector current flowing through the twenty-third resistor and the fourth ESD diode, driving the actual indicator LED to light up. The control chip sends a high / low level signal → the third surface-mount transistor switches → the fourth surface-mount transistor switches → the third transistor switches → the fourth transistor switches → the indicator light turns on / off.

[0046] The working principle of the network switching circuit described in this utility model is as follows:

[0047] The power module starts up, providing a stable operating voltage to the control chip and other active devices. The control chip completes initialization and prepares to receive switching commands. The control chip determines the current network connection strategy based on external commands (such as manual buttons, software commands, or preset logic). This decision determines the conduction state of the switching module (such as an analog switch chip). When connection to the external network connected to the second interface module is required, the control chip commands the switching module to directly connect the second interface to the transformer module. In this case, network data bypasses the control chip's PHY and flows directly to the transformer module through the switching module. When the control chip itself needs to process network data or connect to its internal MAC, the control chip commands the switching module to disconnect the above paths and instead connect the control chip's own MDIx differential signal pin to the transformer module. Data is processed by the control chip before being sent out. Regardless of the signal's origin, it ultimately enters the transformer module. The network transformer within the transformer module couples the signals, performs impedance matching, and provides critical electrical isolation to protect the back-end circuitry from common-mode voltage and surge impacts from network cables. Simultaneously, the protection module provides transient overvoltage protection for the interface. The indicator module is directly controlled by the control chip. The control chip drives the corresponding indicator lights (such as LEDs) to light up in different ways (constantly on, flashing) according to the currently active network path, link status and data activity, providing users with intuitive system status feedback.

[0048] Other structures of the network switching circuit described in this embodiment are available in the prior art.

[0049] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A network switching circuit, characterized in that, include: Power supply module, control chip, switching module, transformer module, protection module, first interface module and second interface module; The power module is connected to the control chip; The control chip is connected to the transformer module via a switching module; The switching module is connected to the second interface module; The transformer module is connected to the protection module and the first interface module, respectively.

2. The network switching circuit according to claim 1, characterized in that, The switching module includes: Analog switch chip, first resistor, second resistor and first capacitor; The DA pin of the analog switch chip is connected to the MDI1+ pin of the control chip; The DB pin of the analog switch chip is connected to the MDI1- pin of the control chip; The DD pin of the analog switch chip is connected to the MDI0- pin of the control chip; The DC pin of the analog switch chip is connected to the MDI0+ pin of the control chip; The VCC pin of the analog switch chip is connected to one end of the first resistor and one end of the first capacitor, respectively. The other end of the first resistor is connected to the power supply module, and the other end of the first capacitor is grounded. The EN pin of the analog switch chip is grounded through a second resistor.

3. The network switching circuit according to claim 2, characterized in that, The transformer module includes: First transformer circuit and second transformer circuit; The first transformer circuit is connected to the second transformer circuit via a switching module.

4. A network switching circuit according to claim 3, characterized in that, The protection module includes a first TVS diode and a second TVS diode. The first TVS diode is connected to the first transformer circuit; The second TVS diode is connected to the second transformer circuit.

5. A network switching circuit according to claim 4, characterized in that, The first transformer circuit includes: First network filter, second capacitor, third capacitor, fourth capacitor, third resistor, fourth resistor, first common-mode filter, first transformer, second common-mode filter and second transformer; The TDP pin of the first network filter is connected to the S1C pin of the analog switch chip and the fourth pin of the first common-mode filter, respectively. The TDN pin of the first network filter is connected to the S1D pin of the analog switch chip and the first pin of the first common-mode filter, respectively. The RDP pin of the first network filter is connected to the S1A pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively. The RDN pin of the first network filter is connected to the S1B pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively. The TDC pin of the first network filter is connected to the third pin of the first transformer and one end of the second capacitor, respectively, and the other end of the second capacitor is grounded. The RDC pin of the first network filter is connected to the third pin of the second transformer and one end of the third capacitor, respectively, and the other end of the third capacitor is grounded; The TXP pin of the first network filter is connected to the first pin of the first TVS diode, and the second pin of the first TVS diode is connected to the first pin of the first transformer. The TXC pin of the first network filter is connected to one end of the third resistor and the sixth pin of the first transformer, respectively, and the other end of the third resistor is grounded through the fourth capacitor; The TXN pin of the first network filter is connected to the third pin of the first TVS diode, and the fourth pin of the first TVS diode is connected to the second pin of the first transformer. The RXP pin of the first network filter is connected to the fifth pin of the first TVS diode, and the sixth pin of the first TVS diode is connected to the first pin of the second transformer. The RXC pin of the first network filter is connected to one end of the fourth resistor and the sixth pin of the second transformer, respectively, and the other end of the fourth resistor is grounded through the fourth capacitor; The RXN pin of the first network filter is connected to the seventh pin of the first TVS diode, and the eighth pin of the first TVS diode is connected to the second pin of the second transformer. The third pin of the first common-mode filter is connected to the fifth pin of the first transformer, and the second pin of the first common-mode filter is connected to the fourth pin of the first transformer. The third pin of the second common-mode filter is connected to the fifth pin of the second transformer, and the second pin of the second common-mode filter is connected to the fourth pin of the second transformer.

6. A network switching circuit according to claim 5, characterized in that, The second transformer circuit includes: Second network filter, fifth capacitor, sixth capacitor, seventh capacitor, fifth resistor, sixth resistor, third common-mode filter, third transformer, fourth common-mode filter and fourth transformer; The TDP pin of the second network filter is connected to the S2C pin of the analog switch chip and the fourth pin of the third common-mode filter, respectively. The TDN pin of the second network filter is connected to the S2D pin of the analog switch chip and the first pin of the third common-mode filter, respectively. The RDP pin of the second network filter is connected to the S2A pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively. The RDN pin of the second network filter is connected to the S2B pin of the analog switch chip and the fourth pin of the second common-mode filter, respectively. The TDC pin of the second network filter is connected to the third pin of the third transformer and one end of the fifth capacitor, respectively, and the other end of the fifth capacitor is grounded; The RDC pin of the second network filter is connected to the third pin of the fourth transformer and one end of the sixth capacitor, respectively, and the other end of the sixth capacitor is grounded; The TXP pin of the second network filter is connected to the first pin of the second TVS diode, and the second pin of the second TVS diode is connected to the first pin of the third transformer. The TXC pin of the second network filter is connected to one end of the fifth resistor and the sixth pin of the third transformer, respectively, and the other end of the fifth resistor is grounded through the seventh capacitor; The TXN pin of the second network filter is connected to the third pin of the second TVS diode, and the fourth pin of the second TVS diode is connected to the second pin of the third transformer. The RXP pin of the second network filter is connected to the fifth pin of the second TVS diode, and the sixth pin of the second TVS diode is connected to the first pin of the fourth transformer. The RXC pin of the second network filter is connected to one end of the sixth resistor and the sixth pin of the third transformer, respectively, and the other end of the sixth resistor is grounded through the seventh capacitor; The RXN pin of the second network filter is connected to the seventh pin of the second TVS diode, and the eighth pin of the second TVS diode is connected to the second pin of the fourth transformer. The third pin of the third common-mode filter is connected to the fifth pin of the third transformer, and the second pin of the third common-mode filter is connected to the fourth pin of the third transformer. The third pin of the fourth common-mode filter is connected to the fifth pin of the fourth transformer, and the second pin of the fourth common-mode filter is connected to the fourth pin of the fourth transformer.

7. A network switching circuit according to claim 6, characterized in that, The power module includes: Power input circuit, first power conversion circuit and second power conversion circuit; The power input circuit is connected to the second power conversion circuit through the first power conversion circuit.

8. A network switching circuit according to claim 7, characterized in that, Also includes: The indicator module includes a first indicator circuit and a second indicator circuit. The first indicator light circuit is connected to the control chip and the second power conversion circuit respectively; The second indicator light circuit is connected to the control chip and the second power conversion circuit.

9. A network switching circuit according to claim 8, characterized in that, The first indicator light circuit includes: First surface mount transistor, second surface mount transistor, eighth resistor, ninth resistor, tenth resistor, eleventh resistor, twelfth resistor, first electrostatic diode, thirteenth resistor, fourteenth resistor, fifteenth resistor, eighth capacitor, first transistor, second transistor, and second electrostatic diode; One end of the eighth resistor is connected to the LED0 / PHYAD0 pin of the control chip; One end of the ninth resistor is connected to the LED0 / PHYAD0 pin of the control chip, and the other end of the ninth resistor is grounded. The base of the first surface-mount transistor is connected to the LED0 / PHYAD0 pin of the control chip. The collector of the first surface-mount transistor is connected to the base of the second surface-mount transistor and one end of the tenth resistor. The other end of the tenth resistor is connected to one end of the eleventh resistor. The emitter of the first surface-mount transistor is grounded. The other end of the eleventh resistor is grounded through the first electrostatic diode, and the other end of the eleventh resistor is connected to the collector of the second surface-mount transistor, and the emitter of the second surface-mount transistor is grounded. One end of the twelfth resistor is connected to the collector of the second surface-mount transistor, and the other end of the twelfth resistor is connected to one end of the thirteenth resistor; The base of the first transistor is connected to the other end of the thirteenth resistor, the emitter of the first transistor is connected to one end of the eighth capacitor and one end of the fourteenth resistor, and the collector of the first transistor and the other end of the eighth capacitor are grounded. The base of the second transistor is connected to the other end of the fourteenth resistor, and the collector of the second transistor is connected to one end of the fifteenth resistor; One end of the second electrostatic diode is connected to the other end of the fifteenth resistor, and the other end of the second electrostatic diode is grounded.

10. A network switching circuit according to claim 9, characterized in that, The first indicator light circuit includes: The third surface mount transistor, the fourth surface mount transistor, the sixteenth resistor, the seventeenth resistor, the eighteenth resistor, the nineteenth resistor, the twentieth resistor, the third electrostatic diode, the twenty-first resistor, the twenty-second resistor, the twenty-third resistor, the ninth capacitor, the third transistor, the fourth transistor, and the fourth electrostatic diode; One end of the sixteenth resistor is connected to the LED1 / PHYAD1 pin of the control chip, and the other end of the sixteenth resistor is connected to the other end of the sixteenth resistor. One end of the seventeenth resistor is connected to the LED1 / PHYAD1 pin of the control chip, and the other end of the seventeenth resistor is grounded. The base of the third surface-mount transistor is connected to the LED1 / PHYAD1 pin of the control chip. The collector of the third surface-mount transistor is connected to the base of the fourth surface-mount transistor and one end of the eighteenth resistor. The other end of the eighteenth resistor is connected to one end of the nineteenth resistor. The emitter of the fourth surface-mount transistor is grounded. The other end of the nineteenth resistor is grounded through the second electrostatic diode, and the other end of the nineteenth resistor is connected to the collector of the fourth surface-mount transistor, and the emitter of the fourth surface-mount transistor is grounded. One end of the twentieth resistor is connected to the collector of the second surface-mount transistor, and the other end of the twentieth resistor is connected to one end of the twentieth eleventh resistor; The base of the third transistor is connected to the other end of the 21st resistor, the emitter of the third transistor is connected to one end of the 9th capacitor and one end of the 22nd resistor, and the collector of the third transistor and the other end of the 9th capacitor are grounded. The base of the fourth transistor is connected to the other end of the second twelfth resistor, and the collector of the fourth transistor is connected to one end of the second thirteenth resistor. One end of the fourth electrostatic diode is connected to the other end of the twenty-third resistor, and the other end of the fourth electrostatic diode is grounded.

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