CN102446616A - Filter circuit and electric connector with same - Google Patents

Abstract

A filter circuit and an electric connector thereof are provided, the filter circuit is provided with a transmission cable side, a circuit board side and a plurality of signal transmission channels, each signal transmission channel comprises a transformer connected to the transmission cable side and two common mode choke coils connected to the transformer and the circuit board side, each transformer comprises a first coil and a second coil, the first coil is provided with two first connecting ends connected to the transmission cable side, the second coil is provided with two second connecting ends connected with the two common mode choke coils and a center tap positioned between the two second connecting ends, the filter circuit is further provided with a plurality of first magnetic core coils, and the center tap of the second coil of each signal transmission channel is electrically connected to the circuit board side through the first magnetic core coil. The signal transmission channel of the filter circuit does not influence Auto MDI/MDIX (automatic port identification function) of external equipment, and the application performance is good.

Description

Filter circuit and electrical connector with the filter circuit

【Technical field】

The invention relates to a filter circuit and an electrical connector with the filter circuit, in particular to a filter circuit applied to a network and an electrical connector with the filter circuit.

【Background technique】

The announcement number of October 17, 2006 is US Patent No. 7123117, the first figure of which discloses a filter circuit, the filter circuit has a transmission cable side and a circuit board side for mutual input and output, and is connected to the two sides Between the first and second signal transmission channels, the second signal transmission channel includes a transformer connected to the transmission cable side and a two-wire common mode choke coil connected to the transformer and the circuit board side, and the transformer includes a first coil and a The second coil, the first coil is provided with two first connection ends connected to the side of the transmission cable, the second coil is provided with two second connection ends connected to one side of the two-wire common mode choke coil and is located at the two second connections terminal, the center tap of the second coil connects directly to the circuit board side.

The center tap of the second coil of the second signal transmission channel is directly connected to the circuit board side. When a current-type driver chip connected to an external device on the circuit board side is used, the second coil of the second signal transmission channel The center tap of the external device is directly connected to the board side, which can cause the AutoMDI/MDIX (port automatic identification function) of this external device to fail, resulting in line interruption, so the application performance of this filter circuit is poor.

【Content of invention】

The purpose of the present invention is to provide a filter circuit with better application performance.

In order to achieve the above object, the filter circuit of the present invention adopts the following technical scheme: a filter circuit, which has a transmission cable side and a circuit board side for mutual input and output, and four transmission channels connected between these two sides, each transmission Each channel includes a transformer connected to the side of the transmission cable and a two-wire common mode choke coil connected to the side of the transformer and the circuit board. The transformer includes a first coil and a second coil. The first coil is connected to the side of the transmission cable. The second coil is provided with two second connection ends connected to the two-wire common mode choke coil and a center tap located between the two second connection ends, and the filter circuit is also provided with a number of first magnetic The core coil, the center taps of the second coils of each transmission channel are electrically connected to the circuit board side through the first core coil.

In order to achieve the above object, the filter circuit of the present invention can also adopt the following technical solutions: a filter circuit, which has a transmission cable side and a circuit board side for mutual input and output, and several transformers and connections connected to the transmission cable side. The signal transmission channel between the transformer and the two-wire common mode choke coil on the circuit board side, the transformer includes a first coil and a second coil, the first coil is provided with two first connection ends connected to the transmission cable side, and the second The coil is provided with two second connection terminals connected to the two-wire common mode choke coil and a center tap located between the two second connection terminals, and the filter circuit is also provided with a plurality of first magnetic core coils, and the signal transmission channel The center tap of the second coil is electrically connected to the circuit board side through the first magnetic core coil.

Compared with the prior art, the filter circuit of the present invention has the following improvements: Since the center tap of the second coil of the signal transmission channel is electrically connected to the circuit board side through the first magnetic core coil, when the filter circuit cooperates with an external device When the current-type drive chip is applied, the signal transmission channel will not affect the Auto MDI/MDIX (port automatic identification function) of the external device, so compared with the prior art, the application performance of the filter circuit of the present invention is better.

Another object of the present invention is to provide an electrical connector with better application performance.

In order to achieve the above object, the electrical connector of the present invention adopts the following technical solutions: an electrical connector, which includes a docking terminal for docking with a pair of connectors, pins for connecting the electrical connector to an external circuit board Terminals and a signal processing module connecting the docking terminal and the pin terminal, the signal processing module includes a plurality of transformers electrically connected to the docking terminal and a two-wire common mode choke coil connecting the transformer and the pin terminal The signal transmission channel, the transformer includes a first coil and a second coil, the first coil is provided with two first connection terminals electrically connected to the docking terminal, and the second coil is provided with two second terminals connected to the two-wire common mode choke coil The connection end and the center tap located between the two second connection ends, the signal processing module is also provided with a number of first magnetic core coils, the center tap of the second coil of the signal transmission channel passes through the first magnetic core The coil is electrically connected to the pin terminal.

In order to achieve the above object, the electrical connector of the present invention can also adopt the following technical solutions: an electrical connector, which includes a docking terminal for docking with a pair of connectors, and a terminal for connecting the electrical connector to an external circuit board. The pin terminal is a signal processing module connected to the docking terminal and the pin terminal. The signal processing module includes four signal transmission channels, and each signal transmission channel includes a transformer electrically connected to the docking terminal and a transformer connected to the transformer. A two-wire common mode choke coil with pin terminals. The transformer includes a first coil and a second coil. The two second connection ends of the mold choke coil and the center tap between the two second connection ends, the signal processing module is also provided with a number of first magnetic core coils, and the center taps of each second coil pass through The first magnetic core coil is electrically connected to a pin terminal.

The center tap of the second coil of the electrical connector of the present invention is electrically connected to the pin terminal through the first magnetic core coil. When the electrical connector is used with a current-type drive chip of an external device connected to the pin terminal, due to The center tap of the second coil of the signal transmission channel is electrically connected to the pin terminal through the first magnetic core coil, and these signal transmission channels will not affect the AutoMDI/MDIX (port automatic identification function) of the external device, overcoming The defect of the signal transmission channel in the background technology is overcome, so the application performance of the electrical connector of the present invention is better.

The present invention will be further described below in conjunction with the accompanying drawings and preferred embodiments.

【Description of drawings】

FIG. 1 is a circuit diagram of a filter circuit according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a filter circuit according to a second embodiment of the present invention.

FIG. 3 is a circuit diagram of a filter circuit according to a third embodiment of the present invention.

FIG. 4 is a circuit diagram of a filter circuit according to a fourth embodiment of the present invention.

Fig. 5 is a perspective view of an electrical connector according to the present invention.

FIG. 6 is a perspective view of the terminal module of the electrical connector according to the present invention from an angle and conforming to the circuit diagram shown in FIGS. 1 to 4 .

7 is a perspective view of another angle of the terminal module of the electrical connector according to the present invention and conforming to the circuit diagram shown in FIG. 1 .

FIG. 8 is a perspective view of another angle of the terminal module of the electrical connector according to the present invention and conforming to the circuit diagram shown in FIG. 2 .

FIG. 9 is a perspective view of another angle of the terminal module of the electrical connector according to the present invention and conforming to the circuit diagram shown in FIG. 3 .

FIG. 10 is a perspective view of another angle of the terminal module of the electrical connector according to the present invention and conforms to the circuit diagram shown in FIG. 4 .

[Description of main component symbols]

Filter circuit 1, 2, 3, 4

Transmission cable side 100

Circuit board side 200

Signal transmission channel 11

Gap discharge circuit 15

Transformer 20, 91

First coil 21

The first connection end 210, 910

Center tap 211, 221, 912

Second Coil 22

The second connection end 220, 911

Two-wire common mode choke coil 30, 92

The first magnetic core coil 40, 94

Third Coil 41

Fourth Coil 42

Electrical connector 5

Insulation body 6

network interface 61

USB interface 62

Terminal module 8

Butt terminal 81

Pin terminal 82

Signal processing module 9

Sub-board 93

【Detailed ways】

Please refer to Fig. 1, the filter circuit 1 according to the first embodiment of the present invention is a network interface circuit, the filter circuit 1 has a transmission cable side 100 and a circuit board side 200 which are input and output to each other and are connected thereto Four signal transmission channels 11 between the two sides. Each signal transmission channel 11 includes a transformer 20 connected to the transmission cable side 100 and a two-wire common mode choke coil 30 connected to the transformer 20 and the circuit board side 200 . The transformer 20 includes a first coil 21 and a second coil 22 , and the first coil 21 and the second coil 22 are coupled to each other. The first coil 21 is provided with two first connection ends 210 connected to the transmission cable side 100 and a center tap 211 located between the two first connection ends 210. The center tap 211 of the first coil 21 of each signal transmission channel 11 is first Short circuit and then connect to a gap discharge circuit 15 and then ground. The second coil 22 has two second connection terminals 220 connected to the two-wire common mode choke coil 30 and a center tap 221 located between the two second connection terminals 220 . The filter circuit 1 is also provided with two first magnetic core coils 40, the first magnetic core coil 40 is a two-wire magnetic core coil, the first magnetic core coil 40 includes a magnetic core (not labeled) and a surrounding The third coil 41 and the fourth coil 42 on the magnetic core are coupled to each other. The center tap 221 of the second coil 22 of one of the signal transmission channels 11 is connected to the circuit board side 200 through the third coil 41 of one of the first magnetic core coils 40, and the second coil 22 of another signal transmission channel 11 The center tap 221 is correspondingly connected to the circuit board side 200 through the fourth coil 42 of one of the first magnetic core coils 40, wherein the center tap 221 of the second coil 22 of the third signal transmission channel 11 is correspondingly connected through the other first coil 40. The third coil 41 of the magnetic core coil 40 is connected to the circuit board side 200, wherein the center tap 221 of the second coil 22 of the fourth signal transmission channel 11 corresponds to the fourth coil 42 passing through the other first magnetic core coil 40 Connect to the circuit board side 200 . In this embodiment, one end of each of the third coils 41 and each of the fourth coils 42 corresponding to the circuit board side 200 is all short-circuited first and then connected to the circuit board side 200, so that it is beneficial to reduce the number of lead-out ends of the circuit board side 200 .

Please refer to FIG. 2 , which discloses a filter circuit 2 according to a second embodiment of the present invention. The filter circuit 2 also has a transmission cable side 100 and a circuit board side 200 which are input and output to each other and a circuit board connected between the two sides. Four signal transmission channels 11 . The filter circuit 2 is different from the filter circuit 1 in that: the filter circuit 2 is provided with a first magnetic core coil 40, and the center taps 221 of the second coils 22 of the two signal transmission channels 11 of the filter circuit 2 pass through the first The third coil 41 of the magnetic core coil 40 is connected to the circuit board side 200, and the center tap 221 of the second coil 22 of the other two signal transmission channels 11 is connected to the circuit board side 200 through the fourth coil 42 of the first magnetic core coil 40 One end of the third coil 41 and the fourth coil 42 of the filter circuit 2 corresponding to the circuit board side 200 is first short-circuited and then connected to the circuit board side 200 , which is also beneficial to reduce the number of lead-out terminals of the circuit board side 200 .

See also shown in Fig. 3, accord with the filter circuit 3 of the third embodiment of the present invention, this filter circuit 3 also has the transmission cable side 100 and the circuit board side 200 of mutual input and output and is connected between these two sides Four signal transmission channels 11 . The filter circuit 3 is different from the filter circuit 1 in that: the filter circuit 3 is provided with a first magnetic core coil 40, and the center taps 221 of the second coils 22 of the three signal transmission channels 11 of the filter circuit 3 pass through the first core coil 40. The third coil 41 of a magnetic core coil 40 is connected to the circuit board side 200, and the center tap 221 of the second coil 22 of the remaining signal transmission channel 11 is connected to the circuit board side 200 through the fourth coil 42 of the first magnetic core coil 40 . In this embodiment, the ends of the third coil 41 and the fourth coil 42 corresponding to the circuit board side 200 are short-circuited first and then connected to the circuit board side 200 , which is also beneficial to reduce the number of lead-out terminals of the circuit board side 200 .

See also shown in Fig. 4, accord with the filter circuit 4 of the 4th embodiment of the present invention, this filter circuit 4 also has the transmission cable side 100 and the circuit board side 200 of mutual input and output and is connected between these two sides Four signal transmission channels 11 . The filter circuit 4 is different from the filter circuit 1 in that: the filter circuit 3 is provided with a first magnetic core coil 40, and the center taps 221 of the second coils 22 of the four signal transmission channels 11 of the filter circuit 3 pass through The third coil 41 of the first core coil 40 is connected to the circuit board side 200 .

Based on the filter circuits of the above four embodiments, the center taps 221 of the second coils 22 of each signal transmission channel are electrically connected to the circuit board side 200 through the first magnetic core coil 40, and the filter circuit can be provided with several (comprising one or more) first magnetic core coils 40, such as four. In addition, the number of signal transmission channels 11 of the filter circuit may be as many (including one or more) as required, but not limited to four. The first magnetic core coil 40 is not limited to a two-wire type magnetic core coil, and it can be a single-wire type or other multi-wire type magnetic core coils. The magnetic core of the first magnetic core coil 40 can be a ferrite core or other types of magnetic cores, and the coil of the first magnetic core coil 40 can be wound by enameled wire or a spiral metal coil or connected by conductive material.

The center tap 221 of the second coil 22 of each signal transmission channel of the filter circuit of the present invention is electrically connected to the circuit board side 200 through the first magnetic core coil 40, and the first magnetic core coil 40 has a certain function of suppressing electromagnetic interference, thereby On the whole, the electromagnetic interference suppression performance of the filter circuit is strong; and when the filter circuit is applied with a current-type drive chip of an external device, since the center tap 221 of the second coil 22 of the signal transmission channel 11 passes through the first magnetic core coil 40 is electrically connected to the circuit board side 200, which will not affect the Auto MDI/MDIX (port automatic identification function) of the external device, and overcomes the defect of the signal transmission channel in the background technology, so the application performance of the filter circuit of the present invention is better .

Please refer to FIGS. 5-7, which is an electrical connector 5 with a filter circuit 1 according to the present invention. The electrical connector 5 is a network connector (RJ45) and a USB connector stacked connector, which includes an insulating body 6 , a shielding case 7 covering the insulating body 6 , and a terminal module 8 mounted on the insulating body 6 . The insulating body 6 includes a network interface 61 and two USB interfaces 62 . The terminal module 8 is provided with a docking terminal 81 (corresponding to the transmission cable side 100) that extends to the network interface 61 and can be docked with a docking connector (not shown), for connecting the electrical connector 5 to an external circuit board ( (not shown) pin terminal 82 (corresponding to the circuit board side 200 ), and the signal processing module 9 connecting the butt terminal 81 and the pin terminal 82 . The signal processing module 9 includes a sub-circuit board 93 welded to the docking terminal 81 and the pin terminal 82, four transformers 91 arranged on the sub-circuit board 93 and electrically connected to the docking terminal 81, and the sub-circuit board Four two-wire common mode choke coils 92 on one side of the sub-circuit board 93 and two first core coils 94 on the opposite side of the sub-circuit board 93 . Each two-wire common mode choke coil 92 is correspondingly connected to a transformer 91 to the pin terminal 82 . The sub-circuit board 93 is provided with a plurality of conductive sheets and conductive lines to connect the butt terminal 81 , the transformer 91 , the two-wire common mode choke coil 92 , the pin terminal 82 , and the first magnetic core coil 94 to form the filter circuit 1 . The four transformers 91 and the four two-wire common mode choke coils 92 constitute four signal transmission channels (corresponding to the four signal transmission channels 11). Specifically, each signal transmission channel includes a 81 transformer 91 and a two-wire common mode choke coil 92 connecting the transformer 91 and the pin terminal 82 . The transformer 91 includes a first coil (not numbered, corresponding to the first coil 21 ) and a second coil (not numbered, corresponding to the second coil 22 ), the first coil is provided with two first connecting ends 910 electrically connected to the docking terminal 81 . The second coil is provided with two second connection terminals 911 connected to the two-wire common mode choke coil 92 and a center tap 912 located between the two second connection terminals 911 . The first magnetic core coil 94 is a two-wire magnetic core coil. The first magnetic core coil 94 includes a magnetic core (not shown) and a third coil (not shown, corresponding to the third coil) that surrounds the magnetic core. 41) Coupling with the fourth coil (not shown, corresponding to the fourth coil 42 ), the third coil and the fourth coil. The center taps 912 of the second coils of the two signal transmission channels are connected to the pin terminal 82 through the third coil and the fourth coil of one of the first magnetic core coils 94 in one-to-one correspondence, and the other two signal transmission channels The center taps 912 of the second coil of the channel are connected to the pin terminal 82 through the third coil and the fourth coil of the other first magnetic core coil 94 in one-to-one correspondence.

Please refer to Fig. 5, Fig. 6 and Fig. 8, the electrical connector 5 with the filter circuit 2 according to the present invention differs from the electrical connector 5 with the filter circuit 1 in that the signal processing module 9 is provided with a The first magnetic core coil 94, the center tap 912 of the second coil of the two signal transmission channels is connected to the pin terminal 82 through the third coil of the first magnetic core coil 94, and the other two signal transmission channels The center tap 912 of the second coil of the first magnetic core coil 94 is correspondingly connected to the pin terminal 82 by the fourth coil of the first magnetic core coil 94 .

Please refer to Fig. 5, Fig. 6 and Fig. 9, the electrical connector 5 with filter circuit 3 according to the present invention differs from the electrical connector 5 with filter circuit 1 in that the signal processing module 9 is provided with a The first magnetic core coil 94, the center tap 912 of the second coil of the three signal transmission channels is connected to the pin terminal 82 through the third coil of the first magnetic core coil 94, and the remaining one signal transmission channel The center tap 912 of the second coil is correspondingly connected to the pin terminal 82 through the fourth coil of the first magnetic core coil 94 .

Please refer to Fig. 5, Fig. 6 and Fig. 10, the electrical connector 5 with the filter circuit 4 according to the present invention differs from the electrical connector 5 with the filter circuit 1 in that the signal processing module 9 is provided with a The center taps 912 of the first magnetic core coil 94 and the second coils of the four signal transmission channels are all connected to the pin terminal 82 through the third coil of the first magnetic core coil 94 .

In the above four embodiments of the electrical connector of the present invention, the first magnetic core coil 94 is a two-wire magnetic core coil, and each of the two-wire common mode choke coils 92 and the first magnetic core coil 94 are The electronic modules are independent of each other and surface mounted on the sub-circuit board 93 . The surface mounted two-wire magnetic core coil is easy to manufacture and install, which is beneficial to reduce costs and occupies a small space.

For the electrical connector of the present invention, the center tap 912 of the second coil of each signal transmission channel of the electrical connector 5 is connected to the pin terminal 82 through the first magnetic core coil, and the signal processing module 9 can be provided with several (including one or more) first magnetic core coils 94, such as four. In addition, the number of the signal transmission channels of the signal processing module 9 can be as many (including one or more) as required, but not limited to four. The first magnetic core coil 94 is not limited to a two-wire type magnetic core coil, and it can be a single-wire type or other multi-wire type magnetic core coils. The magnetic core of the first magnetic core coil 94 can be a ferrite core or other types of magnetic cores, and the coil of the first magnetic core coil 94 can be wound by enameled wire or a spiral metal ring or connected by conductive material.

The center tap 912 of the second coil of the electrical connector of the present invention is electrically connected to the pin terminal 82 through the first magnetic core coil 94, and the first magnetic core coil 94 has a certain function of suppressing electromagnetic interference, thereby making the electrical connector as a whole The electromagnetic interference suppression performance is strong; and when the electrical connector is used in conjunction with a current-type drive chip of an external device connected to the pin terminal 82, since the center tap 912 of the second coil of each signal transmission channel passes through the first A magnetic core coil 94 is electrically connected to the pin terminal 82, which will not affect the Auto MDI/MDIX (port automatic identification function) of the external device, and overcomes the defect of the signal transmission channel of the background technology, so the electrical connector of the present invention application performance is better.

Claims (10)

1. A filter circuit, which has a transmission cable side and a circuit board side that are input and output each other and four transmission channels connected between these two sides, each transmission channel includes a transformer connected to the transmission cable side and The transformer is connected to the two-wire common mode choke coil on the circuit board side, the transformer includes a first coil and a second coil, the first coil is provided with two first connection terminals connected to the transmission cable side, and the second coil is provided with Connecting the two second connection ends of the two-wire common mode choke coil and the center tap between the two second connection ends, it is characterized in that: the filter circuit is also provided with a plurality of first magnetic core coils, and each transmission channel The center taps of the second coil are electrically connected to the circuit board side through the first core coil. 2. The filter circuit according to claim 1, characterized in that: the filter circuit is provided with two first magnetic core coils, the first magnetic core coil comprises a magnetic core and a third coil surrounding the magnetic core The coil and the fourth coil, wherein the center tap of the second coil of one signal transmission channel are connected to the circuit board side through the third coil of one of the first magnetic core coils, wherein the center tap of the second coil of another signal transmission channel The fourth coil corresponding to one of the first magnetic core coils is connected to the circuit board side, wherein the center tap of the second coil of the third signal transmission channel is connected to the third coil corresponding to the other first magnetic core coil. On the circuit board side, the center tap of the second coil of the fourth signal transmission channel is correspondingly connected to the circuit board side through the fourth coil of the other first magnetic core coil. 3. The filter circuit according to claim 1, characterized in that: the filter circuit is provided with a first magnetic core coil, the first magnetic core coil comprises a magnetic core and a third coil wound around the magnetic core With the fourth coil, the center taps of the second coils of the two signal transmission channels are connected to the circuit board side through the third coil, and the center taps of the second coils of the other two signal transmission channels are connected through the first Four coils are connected to the circuit board side. 4. The filter circuit according to claim 1, characterized in that: the filter circuit is provided with a first magnetic core coil, the first magnetic core coil comprises a magnetic core and a third coil wound around the magnetic core With the fourth coil, the center tap of the second coil of the three signal transmission channels is connected to the circuit board side through the third coil, and the center tap of the second coil of the remaining one signal transmission channel is through the fourth coil Connect to the board side. 5. The filter circuit according to claim 1, characterized in that: the filter circuit is provided with a first magnetic core coil, the first magnetic core coil comprises a magnetic core and a third coil wound around the magnetic core As with the fourth coil, the center taps of the second coil of the four signal transmission channels are all connected to the circuit board side through the third coil. 6. A filter circuit, which has a transmission cable side and a circuit board side for mutual input and output, and several transformers connected to the transmission cable side and two-wire common mode chokes connecting the transformer and the circuit board side The signal transmission channel of the coil, the transformer includes a first coil and a second coil, the first coil is provided with two first connection ends connected to the side of the transmission cable, and the second coil is provided with two second terminals connected to the two-wire common mode choke coil Two connecting ends and a center tap located between the two second connecting ends are characterized in that: the filter circuit is also provided with a plurality of first magnetic core coils, and the center tap of the second coil of the signal transmission channel passes through the first magnetic core coil. A magnetic core coil is electrically connected to the circuit board side. 7. An electrical connector, comprising a butt terminal for butt joint with a butt connector, a pin terminal for connecting the electrical connector to an external circuit board, and a signal processing module for connecting the butt terminal and the pin terminal The signal processing module includes several signal transmission channels with a transformer electrically connected to the docking terminal and a two-wire common mode choke coil connected to the transformer and the pin terminal. The transformer includes a first coil and a second coil. Coil, the first coil is provided with two first connection ends electrically connected to the docking terminal, the second coil is provided with two second connection ends connected to the two-wire common mode choke coil and the center between the two second connection ends The tap is characterized in that: the signal processing module is also provided with several first magnetic core coils, and the center tap of the second coil of the signal transmission channel is electrically connected to the pin terminal through the first magnetic core coils. 8. The electrical connector according to claim 7, wherein the signal processing module is further provided with a sub-circuit board, the first magnetic core coil is a two-wire magnetic core coil, and the two-wire Both the common mode choke coil and the first magnetic core coil are electronic modules that are independent from each other and are surface-mounted on the sub-circuit board. 9. An electrical connector, comprising a butt terminal for butt joint with a butt connector, a pin terminal for connecting the electrical connector to an external circuit board, and a signal processing module for connecting the butt terminal and the pin terminal Group, the signal processing module is provided with four signal transmission channels, each signal transmission channel includes a transformer electrically connected to the docking terminal and a two-wire common mode choke coil connected to the transformer and the pin terminal, the transformer It includes a first coil and a second coil, the first coil is provided with two first connection ends electrically connected to the docking terminal, the second coil is provided with two second connection ends connected to the two-wire common mode choke coil and located at the two second The center tap between the two connection ends is characterized in that: the signal processing module is also provided with a number of first magnetic core coils, and the center taps of the second coils of each signal transmission channel pass through the first magnetic core The coil is electrically connected to the pin terminal. 10. The electrical connector according to claim 9, wherein the signal processing module is further provided with a sub-circuit board, the first magnetic core coil is a two-wire magnetic core coil, and each of the two Both the line common mode choke coil and the first magnetic core coil are electronic modules that are independent from each other and are surface-mounted on the sub-circuit board.

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