Discrete transformer network port protection enhancing circuit

Abstract

The utility model relates to the technical field of protection circuits, and discloses a discrete transformer network port protection enhancement circuit with good surge voltage release reliability, which comprises at least one transformer (TR3 and TR4), at least one voltage comparison module (110 and 120) and at least one channel module (130 and 140), signals accessed by the network port are coupled to the PHY chip through the transformers (TR3 and TR4) and the channel modules (130 and 140), when voltage input by the network port is larger than a voltage reference value, the voltage comparison modules (110 and 120) trigger the channel modules (130 and 140) to act and turn off the channel modules (130 and 140), and voltage signals are released to the ground through the transformers (TR3 and TR4).

Description

TECHNICAL FIELD

[0001] The utility model relates to protection circuit technical field more specifically, relate to a kind of discrete transformer network interface protection enhancement circuit. BACKGROUND

[0002] The electronic product using network interface on market is using network transformer before, then the form of discrete component is replaced traditional network transformer, at least one network interface end, external plug-in network cable, signal enters first stage common mode inductor, then again through second stage common mode inductor, after through shelving capacitor to enter PHY chip end, common mode inductor is the electronic component designed to counter electromagnetic interference in circuit, it is actually equivalent to a bidirectional filter, while filtering common mode electromagnetic interference in circuit, also filter the electromagnetic interference emitted by itself to outside, to ensure that other elements in the same circuit are not affected by electromagnetic interference, so the circuit has good inhibitory effect on EMC. However, network interface is external plug-in interface, is easily impacted by surge voltage, this circuit network lacks the release circuit of slightly large energy impact, leading to its lightning surge resistance performance is poor.

[0003] Therefore, how to effectively suppress surge impact, quickly cut off current loop to protect the safety of electronic component work become the technical problem that the technical personnel in the field urgently need to solve. UTILITY MODEL CONTENT

[0004] The technical problem to be solved by the utility model is that the network interface of the prior art is an external plug-in interface, is easily impacted by surge, the circuit network lacks the release circuit of slightly large energy impact, leading to its lightning surge resistance performance is poor, provide a discrete transformer network interface protection enhancement circuit with good surge voltage release reliability.

[0005] The technical scheme adopted by the utility model to solve its technical problem is: a discrete transformer network interface protection enhancement circuit is constructed, which has:

[0006] At least one transformer, one end of one winding is connected with one end of network interface port, and the other end of the one winding is connected with common terminal;

[0007] At least one voltage comparison module, one end of another winding of the transformer is connected with one input end of the voltage comparison module,

[0008] The other input end of the voltage comparison module is connected with reference voltage terminal, for receiving voltage reference value;

[0009] At least one channel module, the other end of another winding of the transformer is connected with one input end of the channel module,

[0010] The other input end of the channel module is connected with the output end of the voltage comparison module,

[0011] The output of the channel module is connected to one end of the PHY chip;

[0012] When the voltage input to the network port is less than the voltage reference value, the signal received at the network port is coupled to the PHY chip via the transformer and the channel module.

[0013] When the voltage input to the network port is greater than the voltage reference value, the voltage comparison module triggers the channel module to shut down, and the voltage signal is released to ground through the transformer.

[0014] In some embodiments, the transformer includes a first transformer.

[0015] One end of one winding of the first transformer is connected to one end of the network port.

[0016] One end of the other winding of the first transformer is connected to one input terminal of the voltage comparison module.

[0017] The other end of the other winding of the first transformer is connected to one input terminal of the channel module.

[0018] The other end of one winding of the first transformer is connected to a common terminal.

[0019] In some embodiments, the transformer further includes a second transformer.

[0020] One end of one winding of the second transformer is connected to the other end of the network port.

[0021] One end of the other winding of the second transformer is connected to the other input terminal of the voltage comparison module.

[0022] The other end of the other winding of the second transformer is connected to the other input terminal of the channel module.

[0023] The other end of one winding of the second transformer is connected to the common terminal.

[0024] In some embodiments, the voltage comparison module includes a first voltage comparator.

[0025] The non-inverting input of the first voltage comparator is connected to one end of the other winding of the first transformer.

[0026] The inverting input of the first voltage comparator is connected to the reference voltage terminal to receive the voltage reference value.

[0027] The output of the first voltage comparator is connected to one input of the channel module.

[0028] In some embodiments, the voltage comparison module further includes a second voltage comparator.

[0029] The non-inverting input of the second voltage comparator is connected to one end of the other winding of the second transformer.

[0030] The inverting input of the second voltage comparator is connected to the reference voltage terminal to receive the voltage reference value.

[0031] The output of the second voltage comparator is connected to the other input of the channel module.

[0032] In some embodiments, the channel module includes a first channel switch.

[0033] One input terminal of the first channel switch is connected to the output terminal of the first voltage comparator.

[0034] The other input terminal of the first channel switch is connected to the other end of the other winding of the first transformer.

[0035] The output terminal of the first channel switch is connected to one end of the PHY chip through a winding of the second-stage common-mode inductor.

[0036] In some embodiments, the channel module further includes a second channel switch.

[0037] One input terminal of the second channel switch is connected to the output terminal of the second voltage comparator.

[0038] The other input terminal of the second channel switch is connected to the other end of the other winding of the second transformer.

[0039] The output terminal of the second channel switch is connected to the other end of the PHY chip through another winding of the second-stage common-mode inductor.

[0040] In some embodiments, the other end of one winding of the first transformer is connected to a common terminal through one end of one winding of the first-stage common-mode inductor.

[0041] The other end of one winding of the second transformer is connected to the common terminal through the other end of one winding of the first common-mode inductor.

[0042] In some embodiments, the voltage comparison module further includes a first resistor and a second resistor connected in series.

[0043] The connection point between the first resistor and the second resistor is connected to the inverting input of the first voltage comparator.

[0044] One end of the second resistor is connected to the VCC power supply terminal.

[0045] The other end of the first resistor is connected with the common end.

[0046] In some embodiments, the voltage comparison module further comprises a fifth resistor and a sixth resistor connected in series,

[0047] The connection end of the fifth resistor and the sixth resistor is connected with the inverting input end of the second voltage comparator,

[0048] One end of the sixth resistor is connected with the VCC power end,

[0049] The other end of the fifth resistor is connected with the common end.

[0050] In the discrete transformer network port protection enhancement circuit, when the voltage input by the network port is less than the voltage reference value, the signal input by the network port is coupled to the PHY chip through the transformer and the channel module, when the voltage input by the network port is greater than the voltage reference value, the voltage comparison module triggers the channel module to act, and the voltage signal is released to the ground through the transformer. Compared with the prior art, the voltage comparison module receives the input voltage signal, and then compares it, when it is greater than the reference value, the channel module is controlled to be turned on, and the high voltage signal is released to the ground through the transformer, the voltage in the initial stage of lightning surge is inductively monitored, and the link loop is cut off in time, so that the damage of components caused by surge impact can be avoided, and the safety of equipment operation is improved. BRIEF DESCRIPTION OF DRAWINGS

[0051] The utility model will be further described below in combination with the drawings and examples, and the drawings are as follows:

[0052] Figure 1 It is the circuit principle drawing of the discrete transformer network port protection enhancement circuit provided by the utility model one embodiment;

[0053] Figure 2 It is the curve graph of the surge voltage provided by the utility model. DETAILED DESCRIPTION

[0054] In order to have more clear understanding of the technical features, purposes and effects of the utility model, the specific implementation mode of the utility model will be described in detail by comparing the drawings.

[0055] As Figures 1-2 As shown in the first embodiment of the discrete transformer network port protection enhancement circuit of the utility model, the discrete transformer network port protection enhancement circuit 10 comprises at least one transformer (TR3 and TR4), at least one voltage comparison module (110 and 120), at least one channel module (130 and 140) and at least one common mode inductor (T1 and T2).

[0056] The transformer (TR3 and TR4) has the functions of isolation, voltage step-up and voltage step-down;

[0057] The voltage comparison module (110 and 120) has a reference voltage value, which can compare the input voltage signal with the reference voltage value, and the size of the two voltages is used to output the high or low level of the voltage, indicating the size relationship of the two input voltages:

[0058] When the voltage of the "+" input end is higher than that of the "-" input end, the voltage comparator outputs a high level;

[0059] When the voltage of the "+" input end is lower than that of the "-" input end, the voltage comparator outputs a low level;

[0060] The channel module (130 and 140) has the functions of signal transmission and shutdown;

[0061] The common mode inductor (T1 and T2) is used to filter electromagnetic interference signals;

[0062] Specifically, one end (corresponding to 3 pins) of one winding of a transformer (corresponding to TR3) is connected to one end of a network port, and one end (corresponding to 2 pins) of one winding of another transformer (corresponding to TR4) is connected to one end of the network port, for receiving network signals (or voltage signals);

[0063] The other end (corresponding to 4 pins) of one winding of a transformer (TR3) is connected to a common end, and the other end (corresponding to 1 pin) of one winding of a transformer (TR4) is connected to the common end. When the transient surge voltage signal is input, the voltage signal can be released to the ground through the other end (corresponding to 1 pin and 4 pin) of one winding of the transformer (TR3 and TR4);

[0064] Further, one input end of a voltage comparison module (corresponding to 110) is connected to one end (corresponding to 2 pins) of the other winding of the transformer (corresponding to TR3), and one input end of another voltage comparison module (corresponding to 120) is connected to one end (corresponding to 3 pins) of the other winding of the transformer (corresponding to TR4), for obtaining the transient surge voltage signal,

[0065] The other input end (corresponding to 3 pins and 6 pins) of the voltage comparison module (110, 120) is connected to the reference voltage end (corresponding to the VCC end), for receiving the voltage reference value, and comparing the surge voltage signal with the voltage reference value, and outputting a high level or low level signal according to the comparison result;

[0066] Further, one input end (corresponding to 4 pins) of a channel module (corresponding to 130) is connected to the other end (corresponding to 1 pin) of the other winding of a transformer (corresponding to TR3), for receiving one network signal (or voltage signal),

[0067] Another end (corresponding to 1 pin) of another winding of another transformer (corresponding to TR4) is connected with an input end (corresponding to 4 pin) of another channel module (corresponding to 140) for receiving another network signal (or voltage signal);

[0068] Another input end (corresponding to 6 pin) of a channel module (corresponding to 130) is connected with an output end (corresponding to 1 pin) of a voltage comparison module (corresponding to 110) for receiving a high level or low level signal,

[0069] Another input end (corresponding to 6 pin) of another channel module (corresponding to 140) is connected with an output end (corresponding to 4 pin) of another voltage comparison module (corresponding to 120) for receiving another high level or low level signal,

[0070] Output ends (corresponding to 3 pin) of the channel modules (130 and 140) are connected with one end of a PHY chip;

[0071] When the voltage input by the network port is less than the voltage reference value, the voltage comparison module (110, 120) outputs low level, the channel module (130 and 140) is in a closed state, and the network signal (or voltage signal) input by the network port is coupled to the PHY chip through the transformer (TR3 and TR4) and the channel module (130 and 140),

[0072] When the voltage input by the network port is greater than the voltage reference value, the voltage comparison module (110, 120) outputs high level, triggering the channel module (130 and 140) to act, and the channel module (130 and 140) is turned off, and the network signal (or voltage signal) is released to the ground through the transformer (TR3 and TR4), so as to ensure the safety of the device operation.

[0073] Using the technical solution, the voltage comparison module (110, 120) receives the input voltage signal and compares it with the reference value, when the voltage is greater than the reference value, the channel module (130 and 140) is controlled to be turned on, and the high voltage signal is released to the ground through the transformer (TR3 and TR4), the voltage in the initial stage of lightning surge is monitored, and the link circuit is cut off in time, so as to avoid damage to the components caused by surge impact, thereby improving the safety of the device operation.

[0074] In some embodiments, as shown in Figure 1 The transformer includes a first transformer TR3, wherein one end (corresponding to 3 pin) of one winding of the first transformer TR3 is connected with one end of the network port for receiving one network signal (or voltage signal),

[0075] One end (corresponding to 2 pin) of another winding of the first transformer TR3 is connected with an input end of a voltage comparison module (corresponding to 110),

[0076] The other end (corresponding to 1 pin) of the other winding of the first transformer TR3 is connected to an input end (corresponding to 4 pin) of a channel module (corresponding to 130), and the first transformer TR3 couples a network signal (or voltage signal) received to a voltage comparison module (corresponding to 110) and the channel module (corresponding to 130),

[0077] The other end (corresponding to 4 pin) of the winding of the first transformer TR3 is connected to the common end.

[0078] In some embodiments, as shown in FIG. 1, the voltage comparison module includes a first voltage comparator U101, wherein the first voltage comparator U101 has a signal comparison and a high-low level signal output function according to the comparison result; Figure 1

[0079] The other end (corresponding to 1 pin) of the other winding of the second transformer TR4 is connected to the other input end (corresponding to 4 pin) of the other channel module (corresponding to 140), and the second transformer TR4 couples another network signal (or voltage signal) received to the other voltage comparison module (corresponding to 120) and the other channel module (corresponding to 140),

[0080] The other end (corresponding to 1 pin) of the other winding of the second transformer TR4 is connected to the other input end (corresponding to 4 pin) of the other channel module (corresponding to 140), and the second transformer TR4 couples another network signal (or voltage signal) received to the other voltage comparison module (corresponding to 120) and the other channel module (corresponding to 140),

[0081] The other end (corresponding to 1 pin) of the other winding of the second transformer TR4 is connected to the other input end (corresponding to 4 pin) of the other channel module (corresponding to 140), and the second transformer TR4 couples another network signal (or voltage signal) received to the other voltage comparison module (corresponding to 120) and the other channel module (corresponding to 140),

[0082] The other end (corresponding to 4 pin) of the winding of the second transformer TR4 is connected to the common end.

[0083] In some embodiments, as shown in FIG. 1, the voltage comparison module includes a first voltage comparator U101, wherein the first voltage comparator U101 has a signal comparison and a high-low level signal output function according to the comparison result; Figure 1

[0084] Specifically, the non-inverting input end (corresponding to 2 pin) of the first voltage comparator U101 is connected to the other end (corresponding to 2 pin) of the other winding of the first transformer TR3 through the fourth resistor R104, for receiving a network signal (or voltage signal),

[0085] The non-inverting input end (corresponding to 3 pin) of the first voltage comparator U101 is connected to the reference voltage end, for receiving a voltage reference value, and comparing the input network signal (or voltage signal) with the voltage reference value, when the network signal (or voltage signal) is greater than the voltage reference value, the first voltage comparator U101 outputs a high level signal, and when the network signal (or voltage signal) is less than the voltage reference value, the first voltage comparator U101 outputs a low level signal; ​​

[0086] The output terminal (pin 1) of the first voltage comparator U101 is connected to an input terminal (pin 6) of a channel module (130) to receive high / low level signals.

[0087] In some implementations, such as Figure 1 As shown, the voltage comparison module also includes a second voltage comparator U102, wherein the non-inverting input terminal (corresponding to pin 5) of the second voltage comparator U102 is connected to one end (corresponding to pin 3) of the other winding of the second transformer TR4 through the eighth resistor R108, and is used to receive another network signal (or voltage signal).

[0088] The inverting input terminal (corresponding to pin 6) of the second voltage comparator U102 is connected to the reference voltage terminal to receive the voltage reference value and compare one of the input network signals (or voltage signals) with the voltage reference value. When the other network signal (or voltage signal) is greater than the voltage reference value, the second voltage comparator U102 outputs a high-level signal; when the other network signal (or voltage signal) is less than the voltage reference value, the second voltage comparator U102 outputs a low-level signal.

[0089] The output terminal (corresponding to pin 4) of the second voltage comparator U102 is connected to the other input terminal (corresponding to pin 6) of another channel module (corresponding to 140) to receive high / low level signals.

[0090] In some implementations, such as Figure 1 As shown, the channel module includes a first channel switch U103, which serves as a channel selection switch.

[0091] Specifically, one input terminal (pin 5) of the first channel switch U103 is connected to the output terminal (pin 1) of the first voltage comparator U101 to receive high / low level signals.

[0092] The other input terminal (corresponding to pin 2) of the first channel switch U103 is connected to the other end (corresponding to pin 1) of the other winding of the first transformer TR3. The first transformer TR3 will receive one network signal (or voltage signal) and couple it to the first channel switch U103.

[0093] The output terminal (corresponding to pin 3) of the first channel switch U103 is connected to one end of the winding of the second stage common mode circuit T2 (corresponding to pin 1) and the first capacitor C101 to one end of the PHY chip.

[0094] When pin 5 of the first channel switch U103 is high, that is, along with pins 1-4, the signal channel is open and does not form a surge impact loop.

[0095] When the 5 pin is low, i.e. the induced voltage does not exceed the threshold, at this time the signal channel passes through the 3-4 pin of the first channel switch U103, and is in a connected state.

[0096] In some embodiments, as shown in Figure 1 The channel module further includes a second channel switch U104, wherein an input end (corresponding to the 5 pin) of the second channel switch U104 is connected to an output end (corresponding to the 4 pin) of the second voltage comparator U102, for receiving a high / low level signal,

[0097] Another input end (corresponding to the 2 pin) of the second channel switch U104 is connected to another end (corresponding to the 1 pin) of another winding of the second transformer TR4, and the second transformer TR4 receives another network signal (or voltage signal) and outputs the same to the second channel switch U104.

[0098] An output end (corresponding to the 3 pin) of the second channel switch U104 is connected to another end of the PHY chip through another winding (corresponding to the 4 pin) of the second common-mode inductor T2 and the second capacitor C102.

[0099] When the 5 pin of the second channel switch U104 is high, i.e. the 1-4 pin is connected, at this time the signal channel is disconnected, and does not form a loop for a surge impact;

[0100] When the 5 pin is low, i.e. the induced voltage does not exceed the threshold, at this time the signal channel passes through the 3-4 pin of the second channel switch U104, and is in a connected state, through the induction monitoring of the voltage in the starting stage of the lightning surge, the link loop is timely cut off, and the damage of components caused by the surge impact can be effectively avoided.

[0101] In some embodiments, as shown in Figure 1 Another end (corresponding to the 4 pin) of one winding of the first transformer TR3 is connected to the common end through one end (corresponding to the 3 pin) of one winding of the first common-mode inductor T1,

[0102] Another end (corresponding to the 1 pin) of one winding of the second transformer TR4 is connected to the common end through the other end (corresponding to the 1 pin) of one winding of the first common-mode inductor T1.

[0103] In some embodiments, as shown in Figure 1 In order to obtain a reliable reference voltage signal, a first resistor R101 and a second resistor R102 can be arranged in a voltage comparison module (corresponding to 110),

[0104] The first resistor R101 and the second resistor R102 are connected in series

[0105] The connection end of the first resistor R101 and the second resistor R102 is connected with the inverting input end (corresponding to 3 pin) of the first voltage comparator U101,

[0106] One end of the second resistor R102 is connected with the VCC power supply end,

[0107] The other end of the first resistor R101 is connected with the common end.

[0108] The voltage signal inputted by the VCC power supply end is divided by the first resistor R101 and the second resistor R102, and then inputted to the inverting input end (corresponding to 3 pin) of the first voltage comparator U101 as a reference signal.

[0109] In some embodiments, as Figure 1 Figure 1 shown, in order to obtain a reliable reference voltage signal, the fifth resistor R105 and the sixth resistor R106 can be arranged in another voltage comparison module (corresponding to 120),

[0110] The fifth resistor R105 and the sixth resistor R106 are connected in series,

[0111] The connection end of the fifth resistor R105 and the sixth resistor R106 is connected with the inverting input end (corresponding to 6 pin) of the second voltage comparator U102,

[0112] One end of the sixth resistor R106 is connected with the VCC power supply end,

[0113] The other end of the fifth resistor R105 is connected with the common end,

[0114] The voltage signal inputted by the VCC power supply end is divided by the fifth resistor R105 and the sixth resistor R106, and then inputted to the inverting input end (corresponding to 6 pin) of the second voltage comparator U102 as a reference signal.

[0115] The embodiments of the utility model are described above in combination with the drawings, but the utility model is not limited to the above-mentioned specific embodiments, and the above-mentioned specific embodiments are only illustrative but not restrictive, and the person skilled in the art can make many forms under the inspiration of the utility model without departing from the purpose of the utility model and the scope protected by the claims, and these all belong to the protection of the utility model.

Claims

1. A discrete transformer network port protection enhancement circuit, characterized in that, comprises: at least one transformer, one end of one winding of which is connected to one end of a network port, the other end of the one winding being connected to a common end; at least one voltage comparison module, one input end of which is coupled to one end of another winding of the transformer, the other input end of the voltage comparison module being connected to a reference voltage end for receiving a voltage reference value; at least one channel module, one input end of which is connected to the other end of the other winding of the transformer, the other input end of the channel module being connected to the output end of the voltage comparison module, the output end of the channel module being connected to one end of a PHY chip; when the voltage input by the network port is less than the voltage reference value, the signal input by the network port is coupled to the PHY chip through the transformer and the channel module, when the voltage input by the network port is greater than the voltage reference value, the voltage comparison module triggers the channel module to act, and the channel module is turned off, and the voltage signal is released to the ground through the transformer.

2. The discrete transformer network port protection enhancement circuit according to claim 1, wherein the transformer comprises a first transformer, one end of one winding of the first transformer is connected to one end of the network port, one end of another winding of the first transformer is connected to one input end of the voltage comparison module, the other end of the other winding of the first transformer is connected to one input end of the channel module, the other end of one winding of the first transformer is connected to the common end.

3. The discrete transformer network port protection enhancement circuit according to claim 2, wherein the transformer further comprises a second transformer, one end of one winding of the second transformer is connected to the other end of the network port, one end of another winding of the second transformer is connected to the other input end of the voltage comparison module, the other end of the other winding of the second transformer is connected to the other input end of the channel module, the other end of one winding of the second transformer is connected to the common end.

4. The discrete transformer network port protection enhancement circuit according to claim 3, wherein the voltage comparison module comprises a first voltage comparator, the non-inverting input end of the first voltage comparator is connected to one end of the other winding of the first transformer, the inverting input end of the first voltage comparator is connected to the reference voltage end for receiving the voltage reference value, the output end of the first voltage comparator is connected to one input end of the channel module.

5. The discrete transformer network port protection enhancement circuit according to claim 4, wherein the voltage comparison module further comprises a second voltage comparator, the non-inverting input end of the second voltage comparator is connected to one end of the other winding of the second transformer, the inverting input end of the second voltage comparator is connected to the reference voltage end for receiving the voltage reference value, the output end of the second voltage comparator is connected to the other input end of the channel module.

6. The discrete transformer network port protection enhancement circuit according to claim 5, wherein the channel module comprises a first channel switch, An input terminal of the first channel switch is connected with an output terminal of the first voltage comparator, Another input terminal of the first channel switch is connected with another end of another winding of the first transformer, An output terminal of the first channel switch is connected with one end of the PHY chip through a winding of the second stage common mode inductor.

7. The discrete transformer POE enhancement circuit of claim 6, wherein, The channel module further comprises a second channel switch, An input terminal of the second channel switch is connected with an output terminal of the second voltage comparator, Another input terminal of the second channel switch is connected with another end of another winding of the second transformer, An output terminal of the second channel switch is connected with another end of the PHY chip through another winding of the second stage common mode inductor.

8. The discrete transformer POE enhancement circuit of claim 6, wherein, Another end of the winding of the first transformer is connected with the common terminal through one end of a winding of the first stage common mode inductor, Another end of the winding of the second transformer is connected with the common terminal through another end of the winding of the first stage common mode inductor.

9. The discrete transformer POE enhancement circuit of claim 7, wherein, The voltage comparison module further comprises a first resistor and a second resistor connected in series, The connection terminal of the first resistor and the second resistor is connected with the inverting input terminal of the first voltage comparator, One end of the second resistor is connected with the VCC power terminal, Another end of the first resistor is connected with the common terminal.

10. The discrete transformer POE enhancement circuit of claim 9, wherein, The voltage comparison module further comprises a fifth resistor and a sixth resistor connected in series, The connection terminal of the fifth resistor and the sixth resistor is connected with the inverting input terminal of the second voltage comparator, One end of the sixth resistor is connected with the VCC power terminal, Another end of the fifth resistor is connected with the common terminal.

Images