CN116706580A - FPC-based multi-channel RF connector - Google Patents

Abstract

The present disclosure provides a multichannel radio frequency connector based on FPC, characterized by comprising: the FPC flexible flat cable comprises a plurality of paths of radio frequency signal paths; the metal structural part is provided with a plurality of radio frequency signal through holes, and a radio frequency signal spring needle is fixedly supported in each radio frequency signal through hole through an insulator; a plurality of grounding spring pins are uniformly arranged around each radio frequency signal through hole; the radio frequency signal spring needle and the grounding spring needle are configured to be elastically connected to the opposite-end connecting component and/or the FPC flexible flat cable, so that radio frequency signals are transmitted through the radio frequency signal spring needle.

Description

FPC-based multi-channel RF connector

technical field

The present disclosure relates to the technical fields of communication and radio frequency connectors, in particular to a high-density FPC multi-channel radio frequency connector.

Background technique

FPC (Flexible Printed Circuit) is a highly reliable and excellent flexible printed circuit board made of polyimide (PI) or polyester film as the base material. It is generally used for transmission of high-speed, Digital signal or voltage, current signal. For external input and output, it needs to be used in conjunction with the connector to achieve the purpose of signal transmission. The FPC multi-channel connectors currently on the market are mainly designed for high-speed signals and are not suitable for RF signal transmission scenarios. RF connectors are mostly coaxial structures, and their main electrical characteristics include characteristic impedance, VSWR, insertion loss, RF leakage, and frequency of use. The current FPC connectors on the market cannot meet the requirements of the relevant characteristics of radio frequency connectors, so the function of transmitting radio frequency signals cannot be realized.

Theoretically, in some scenarios, the RF connectors used for PCB hard boards can also be used for FPC soft boards. The Chinese patent with the application number 202011263889.4 discloses a multi-channel radio frequency connector on the PCB board end, which forms a high-density multi-channel radio frequency connector assembly by integrating multiple channels of a single coaxial connector.

The above scheme is still the traditional radio frequency connector male-female pairing scheme, the height after mating is relatively high, and the connector density is constrained by the structure and process capability, it is difficult to break through the standard interface size of the connector, and it is impossible to achieve a more extreme high-density scene , such as the scene where the distance between the centers of the connectors is less than 2mm or smaller; in addition, there is a certain insertion force when the male and female are plugged in, and the insertion force increases exponentially when multiple groups are integrated, resulting in difficulties in installation and insertion, and Easily damaged by force.

Contents of the invention

Based on the above problems, the present disclosure provides an FPC-based multi-channel radio frequency connector to alleviate the above technical problems in the prior art.

(1) Technical solution

The present disclosure provides an FPC-based multi-channel radio frequency connector, including: FPC flexible cable, including multiple radio frequency signal paths; The insulator support is fixed with radio frequency signal spring pins; a plurality of ground spring pins are evenly arranged around each radio frequency signal through hole; wherein, the radio frequency signal spring pins and the ground spring pins are configured to be elastically connected to the opposite end connection part and/or the FPC flexible Arrange the wires to realize the transmission of radio frequency signals through radio frequency signal pins.

According to an embodiment of the present disclosure, types of the radio frequency signal pins and the grounding pins include split double-ended pins, split single-ended pins, and integrated elastic pins.

According to an embodiment of the present disclosure, the tip of the probe of the radio frequency signal pin and/or the grounding pin extends out of the metal structure so as to be connected with the opposite end connection component and/or the FPC flexible cable.

According to an embodiment of the present disclosure, each radio frequency signal through hole is arranged coaxially with the insulator and the radio frequency signal spring pin disposed in the radio frequency signal through hole.

According to an embodiment of the present disclosure, the FPC flexible cable includes three metal film layers and two dielectric substrate layers sandwiched between the three metal film layers, and gold fingers are provided at the end of the FPC flexible cable.

According to an embodiment of the present disclosure, the metal thin film layer located on the upper and lower surface layers of the FPC flexible cable is a metal ground, and the middle metal thin film layer is a radio frequency signal transmission layer and is provided with multiple radio frequency signal paths.

According to an embodiment of the present disclosure, metallized via hole arrays are arranged at equal intervals between adjacent radio frequency signal paths for signal shielding between adjacent radio frequency signal paths.

According to an embodiment of the present disclosure, the FPC flexible cable is connected in parallel to the mounting surface of the opposite connecting part through the radio frequency signal spring pin and the grounding spring pin, or the FPC flexible cable is vertically connected to the opposite end connecting part through the radio frequency signal spring pin and the grounding spring pin Mounting surface.

According to an embodiment of the present disclosure, the FPC-based multi-channel radio frequency connector further includes a metal shielding cover, and the metal shielding cover is arranged on the gold finger and the metal structure of the FPC flexible cable, and is configured to have shielding isolation ribs for FPC Signal isolation between adjacent RF signal channels of gold fingers.

According to an embodiment of the present disclosure, the FPC-based multi-channel radio frequency connector further includes a positioning pin and a fastening structure configured for positioning and connecting the metal structural member and the opposite connecting part and/or the FPC flexible cable.

(2) Beneficial effects

It can be seen from the above technical solutions that the FPC-based multi-channel radio frequency connector of the present disclosure has at least one or part of the following beneficial effects:

(1) Solved the problem of joint docking of FPC flexible cable used to transmit multi-channel RF signals, and provided a solution for FPC RF connectors;

(2) The connector adopts a 50-ohm coaxial structure for direct docking, canceling the traditional male-female standard interface docking form, which is easy to achieve a more extreme miniaturization and high-density design;

(3) The elastic contact method of the spring needle is used to realize the repeated pluggable docking, and avoid the problems of difficult installation and disassembly caused by excessive plugging force when the multi-channel male-female connector is docked, and easy to be damaged by force;

(4) From the isolation design between FPC flexible cable channels to the shielding design at the joint, the high isolation characteristics of the FPC RF connector are double guaranteed.

Description of drawings

FIG. 1 is a schematic diagram of a docking scene of an FPC-based multi-channel radio frequency connector according to an embodiment of the present disclosure;

2a is a schematic diagram of the end face structure of the metal structure of the FPC-based multi-channel radio frequency connector according to the embodiment of the present disclosure;

FIG. 2b is a schematic side view of a metal structure of an FPC-based multi-channel radio frequency connector according to an embodiment of the present disclosure;

FIG. 2c is a schematic cross-sectional structural view of the metal structure of the FPC-based multi-channel radio frequency connector according to the embodiment of the present disclosure cut along A'-A;'

3 is a schematic diagram of a docking scene of an FPC-based multi-channel radio frequency connector according to another embodiment of the present disclosure;

4a is a schematic top view of a metal structure of an FPC-based multi-channel radio frequency connector according to another embodiment of the present disclosure;

FIG. 4b is a schematic diagram of the front structure of the metal shielding cover of the FPC-based multi-channel radio frequency connector according to another embodiment of the present disclosure;

4c is a schematic diagram of the back structure of the metal shielding cover of the FPC-based multi-channel radio frequency connector according to another embodiment of the present disclosure;

Fig. 4d is a schematic diagram of the end face structure of the metal structure of the FPC-based multi-channel radio frequency connector according to another embodiment of the present disclosure;

Fig. 4e is a schematic cross-sectional structure diagram of a metal structure of an FPC-based multi-channel radio frequency connector cut along B'-B according to another embodiment of the present disclosure;

Fig. 5a is a schematic diagram of the pin contacts of the radio frequency signal pin and the grounding pin on the opposite end connection part of the disclosed embodiment;

Fig. 5b is a schematic side view of the spring pin contact shown in Fig. 5a;

FIG. 6a is a schematic top view of the FPC flexible cable according to an embodiment of the present disclosure;

6b is a schematic cross-sectional structure diagram of an FPC flexible cable according to an embodiment of the present disclosure;

FIG. 6c is a schematic top view of an FPC flexible cable according to another embodiment of the present disclosure;

6d is a schematic cross-sectional structure diagram of an FPC flexible cable according to another embodiment of the present disclosure;

Fig. 7a is a schematic structural diagram of a split-type double-ended probe according to an embodiment of the present disclosure;

Fig. 7b is a schematic structural diagram of a split-type single-head probe according to an embodiment of the present disclosure;

Fig. 7c is a schematic structural view of the integrated elastic pin according to the embodiment of the present disclosure.

[Description of main component symbols of the embodiment of the present disclosure in the accompanying drawings]

1-FPC flexible cable; 2-metal structural parts; 3-connecting parts at the opposite end; 4-radio frequency signal pin; 5-grounding pin; 6-insulator; 7-metal shielding cover; 701-shielding isolation rib; Positioning pin; 801 positioning pin hole; 9-fastening screw hole; 10-metal film layer; 11-dielectric substrate layer; 12-metallized via hole; 13-RF signal contact; 14-ground contact; 15- Indium bumps; 16-double-ended bullet; 17-single-ended bullet; 18-integrated elastic; 19-miniature spring; 20-probe.

Detailed ways

The present disclosure provides an FPC-based multi-channel radio frequency connector, which is mainly used to improve the connection problem of radio frequency signals of FPC flexible cables, especially the connection problem of multi-channel radio frequency signals based on FPC under high density conditions.

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

In an embodiment of the present disclosure, an FPC-based multi-channel radio frequency connector is provided, with reference to Figures 1, 3, 2a-2c, 4a-4e, 5a-5b, 6a-6d, As shown in Figures 7a-7c, the FPC-based multi-channel radio frequency connector includes:

FPC flexible cable 1, including multiple radio frequency signal paths; and

The metal structure 2 is provided with a plurality of radio frequency signal through holes, and a radio frequency signal pin 4 is supported and fixed in each radio frequency signal through hole by an insulator 6; a plurality of grounding pins 5 are uniformly arranged around each radio frequency signal through hole;

Wherein, the radio frequency signal pin 4 and the grounding pin 5 are configured to be elastically connected to the opposite connecting part 3 and/or the FPC flexible cable 1 , so as to realize the transmission of the radio frequency signal through the radio frequency signal pin 4 .

According to an embodiment of the present disclosure, the dielectric substrate layer 11 of the FPC flexible cable may be a polyimide (PI) film, or may be a polyester film or the like. The metal film layer 10 of the FPC flexible cable can be a conventional brass film, or a metal film layer with low thermal conductivity such as beryllium copper, constantan, manganese copper, etc., so as to achieve low heat leakage performance; the metal film layer of the FPC flexible cable can also be It can be a superconducting metal thin film layer, such as niobium film, niobium titanium film, etc., so as to achieve ultra-low heat leakage and ultra-low loss characteristics, and is very suitable for signal reading circuits.

According to the embodiment of the present disclosure, as shown in Figure 2c and Figure 4e, each radio frequency signal through hole of the metal structure 2 is coaxially arranged with the insulator 6 and the radio frequency signal spring pin 4 arranged in the radio frequency signal through hole, and is designed as 50 ohm standard characteristic impedance. The ground spring pin 5 does not need an insulator, but is directly assembled in contact with the metal structure 2 . The ground pins 5 are evenly distributed around the radio frequency signal pins 4, and are used for signal isolation and shielding between channels. In order to improve the signal density, the ground pin 5 can be shared in the middle of adjacent channels.

According to the embodiment of the present disclosure, as shown in Figures 7a-7c, the types of the radio frequency signal pin 4 and the grounding pin 5 include a split type double-headed pin 16, a split type single-headed pin 17, and an integrated elastic pin 18 ( That is, there is no discontinuity inside the needle). A miniature spring 19 is arranged in the housing or groove of the main body of the split type double-ended spring pin 16 , and probes 20 are respectively connected to both ends of the miniature spring 19 , so that the probe 20 can be elastically connected to the miniature spring 19 . The tip of the probe 20 can be configured in different structures according to practical applications. A miniature spring 19 is arranged in the housing or groove of the main body of the split-type single-headed spring pin 17 , and one end of the miniature spring 19 is connected with a probe 20 , so that the probe 20 can be elastically connected to the miniature spring 19 . The other end of the shell or groove of the main body is blocked. The middle part of the one-piece elastic spring needle 18 is provided with a spring structure, and the two ends of the spring structure are provided as probes 20 . This allows the probes 20 at both ends to be elastically connected to the opposite connecting component 3 and/or the FPC flexible cable 1 . The aforementioned miniature springs and integral elastic parts can also be replaced by fur buttons or other elastic parts; the probes at both ends of the above-mentioned elastic pins have pointed features, so as to provide more stable and reliable contact force during elastic contact. The material of the above spring pin can be beryllium copper, which has excellent properties such as high elasticity, wear resistance, fatigue resistance and stress relaxation resistance.

According to an embodiment of the present disclosure, the tip of the probe 20 of the RF signal pin 4 and/or the grounding pin 5 extends out of the metal structure so as to be connected to the opposite end connecting component 2 and/or the FPC flexible cable 1 .

According to the embodiment of the present disclosure, as shown in Figure 1 and Figure 2a-2c, the FPC flexible cable is connected in parallel to the mounting surface of the opposite end connecting component through the radio frequency signal pin and the grounding pin, that is, the FPC flexible cable is 180° Parallel to the mounting surface of the connecting part at the opposite end; then the spring pin array composed of the radio frequency signal spring pin and the grounding spring pin assembled on the metal structure 2 is perpendicular to the two mounting surfaces, and elastically contacts with the contacts on the two mounting surfaces at the same time For example, the probe 20 at one end is in elastic contact with the RF signal contact 13 and the ground contact 14 on the mounting surface of the connecting component 3 at the opposite end, and the probe 20 at the other end is elastically connected or welded to the FPC flexible cable. At this time, the metal structural part 2 is located between the two installation surfaces of the opposite end connecting part 3 and the FPC flexible cable 1, similar to a sandwich sandwich structure. The metal structural part 2, the FPC flexible cable 1, and the connecting part 3 at the opposite end are assembled and fixed together by means of fasteners such as screws. Precise positioning structural features are required in the assembly process to ensure precise alignment under high-density conditions. The fine positioning pins can be made on the metal structural parts, and the FPC flexible cable 1 and the connecting part 3 at the opposite end are provided with pin holes and screw holes in corresponding positions.

Or as shown in Figure 3, Figure 4a-Figure 4d, the FPC flexible cable is vertically connected to the mounting surface of the opposite end connecting component through the radio frequency signal pin and the grounding pin, that is, the FPC flexible cable is installed perpendicular to the opposite end at 90° noodle. At this time, one end of the radio frequency signal spring pin 4 is welded to the gold finger of the FPC flexible cable, and the other end is in elastic contact with the radio frequency signal contact 13 on the mounting surface of the opposite end connecting component 3 to be connected. Only one end of the grounding pin needs to be extended. For example, if the split type single-headed pin 17 is selected, the probe 20 of the split-type single-ended pin 17 is in elastic contact with the grounding contact 14 . At this time, a metal shielding cover 7 needs to be provided on the metal structure 2 , and the metal structure 2 is divided into two parts as a whole, so that the FPC flexible cable 1 is sandwiched between the metal structure 2 and the metal shielding cover 7 . Shielding isolation ribs 701 are equally spaced on the metal shielding cover 7 for signal isolation between adjacent channels of the FPC gold fingers. The FPC flexible cable 1, the metal structure and the metal shielding cover are assembled together by screw fastening or welding to form an FPC radio frequency connector assembly. Precise positioning structural features are required in the assembly process to ensure precise alignment under high-density conditions. The positioning pins are preferably made on metal structural parts, and screw holes and positioning pin hole features are provided at corresponding positions on the FPC flexible cable 1 and the metal shielding cover 7 .

The radio frequency signal contact 13 and the ground contact 14 of the above-mentioned opposite-end connection part correspond to the layout of the radio frequency signal spring pin and the ground spring pin on the metal structure one by one, and the radio frequency signal contact 13 is surrounded by a circle of ground contact 14. The ground contact 14 is shared between adjacent channels. In order to reduce the contact resistance between the radio frequency signal pin 4 and the radio frequency signal contact, indium bumps 15 can be added on the contact.

According to an embodiment of the present disclosure, as shown in Figures 6a-6d, the FPC flexible cable includes three layers of metal film layers 10 and two layers of dielectric substrate layers 11 sandwiched between the three layers of metal film layers, the FPC flexible cable The ends of the wires are provided with gold fingers (as shown in the area on the left of Figure 6a and Figure 6c). Gold fingers are used to connect circuits and/or pass signals. The metal thin film layer 10 located on the upper and lower surfaces of the FPC flexible cable is a metal ground, and the middle metal thin film layer 10 is a radio frequency signal transmission layer and is provided with multiple radio frequency signal paths. An array of metallized via holes 12 is arranged at equal intervals between adjacent radio frequency signal paths, and the array of metallized via holes 12 is used for signal shielding between adjacent radio frequency signal paths.

According to an embodiment of the present disclosure, as shown in Figures 6a to 6d, the FPC flexible cable 1 includes two typical types of transmission lines, namely the coplanar waveguide transmission line as shown in Figures 6a and 6b, and the coplanar waveguide transmission line as shown in Figures 6c and 6d The stripline transmission line shown. When the signal line of the middle metal thin film layer 10 reaches the terminal connection position, it can pass through the metallized via hole 12 to transition to the gold finger of the surface layer. N channels of radio frequency signal lines are evenly distributed on the FPC flexible cable 1 , and metallized through holes 12 are arranged at equal intervals between adjacent radio frequency signal channels for signal shielding and channel isolation. The signal transmission line of each radio frequency signal path is set to a standard characteristic impedance of 50 ohms.

According to the embodiment of the present disclosure, as shown in Figure 3, Figure 4a, Figure 4b, and Figure 4c, the FPC-based multi-channel radio frequency connector also includes a metal shielding cover 7, and the metal shielding cover 7 is arranged on the FPC flexible cable The gold finger and the metal structure 2 are configured to have shielding isolation ribs 701 for signal isolation between adjacent radio frequency signal channels. The multi-channel radio frequency connector also includes a positioning pin 8 and a fastening structure, which are configured for positioning and connecting the metal structure 2 and the opposite connecting part 3 and/or the FPC flexible cable 1 . For example, through positioning pin 8 and the opposite end connection part 3 and/or FPC flexible cable 1 and/or the positioning pin hole 801 on the metal shielding cover, and then fixedly connected through the fastening structure, for example, the fastening structure may include through Fastening bolts are installed in the fastening screw holes 9 for fixed connection, such as fastening the metal structure 2 to the opposite connecting part 3 , or fastening the metal structure 2 to the metal shielding cover 7 .

According to the embodiment of the present disclosure, N+1 shielding isolation ribs 7 may be provided on the metal shielding cover 7 to completely isolate and shield signals between adjacent channels of the FPC flexible cable, thereby ensuring a high isolation index. At the same time, the metal shielding cover 7 has features of positioning pin holes 801 and fastening screw holes 9 .

According to the embodiment of the present disclosure, after the flexible wire 1, the metal structural part 2 and the opposite connecting part 3 are locked by the fastening structure, the radio frequency signal pin 4 and the ground pin 5 are compressed to generate elastic force, so that the radio frequency pin The pin 4 and the ground spring pin 5 are in stable and reliable contact with the radio frequency signal contact 13 and the ground contact 14 respectively.

According to an embodiment of the present disclosure, the above-mentioned metal structure 2 and the metal shielding cover 7 may be made of copper alloys such as brass and phosphor bronze.

According to an embodiment of the present disclosure, the material of the above-mentioned insulator 6 may be Teflon or polyimide PI, or may be sintered glass beads.

According to the embodiment of the present disclosure, the array composed of the radio frequency signal pins 4 and the grounding pins 5 can be arranged arbitrarily according to actual demand scenarios.

So far, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. It should be noted that, in the accompanying drawings or in the text of the specification, implementations that are not shown or described are forms known to those of ordinary skill in the art, and are not described in detail. In addition, the above definitions of each element and method are not limited to the various specific structures, shapes or methods mentioned in the embodiments, and those skilled in the art can easily modify or replace them.

According to the above description, those skilled in the art should have a clear understanding of the FPC-based multi-channel radio frequency connector of the present disclosure.

In summary, the present disclosure provides an FPC-based multi-channel radio frequency connector, which realizes efficient signal transmission for interconnection between PCBs, and can be used for large-scale expansion of low-temperature connections for superconducting quantum computing.

It should also be noted that the above are different embodiments provided by the present disclosure. These embodiments are used to illustrate the technical content of the present disclosure, rather than to limit the protection scope of the present disclosure. A feature of one embodiment can be applied to other embodiments through appropriate modification, replacement, combination, and separation.

It should be noted that, unless otherwise specified herein, having “a” element is not limited to having a single element, but may include one or more elements.

In this article, unless otherwise specified, the so-called feature A "or" (or) or "and/or" (and/or) feature B means that nails exist alone, B exists alone, or A and B exist simultaneously ; The so-called feature A "and" (and) or "and" (and) or "and" (and) feature B means that nail and B exist at the same time; the so-called "include", "include", "have", " Contains" means including but not limited to.

In addition, unless specifically described or steps that must occur sequentially, the order of the above steps is not limited to that listed above and may be changed or rearranged according to the desired design. Moreover, the above-mentioned embodiments can be mixed and matched with each other or with other embodiments based on design and reliability considerations, that is, technical features in different embodiments can be freely combined to form more embodiments.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present disclosure in detail. It should be understood that the above descriptions are only specific embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included within the protection scope of the present disclosure.

Claims (10)

1. A FPC-based multichannel radio frequency connector, comprising:

the FPC flexible flat cable comprises a plurality of paths of radio frequency signal paths; and

the metal structural part is provided with a plurality of radio frequency signal through holes, and a radio frequency signal spring needle is fixedly supported in each radio frequency signal through hole through an insulator; a plurality of grounding spring pins are uniformly arranged around each radio frequency signal through hole;

the radio frequency signal spring needle and the grounding spring needle are configured to be elastically connected to the opposite-end connecting component and/or the FPC flexible flat cable, so that radio frequency signals are transmitted through the radio frequency signal spring needle.

2. The FPC-based multichannel radio frequency connector of claim 1, wherein the types of radio frequency signal pins and ground pins include split double-ended pins, split single-ended pins, integral elastic pins.

3. The FPC-based multichannel radio frequency connector according to claim 1, wherein tip positions of the probes of the radio frequency signal pins and/or the ground pins extend out of the metal structural member to be connected with the opposite end connection member and/or the FPC flexible flat cable.

4. The FPC-based multichannel radio frequency connector according to claim 1, wherein each radio frequency signal via is coaxially arranged with an insulator, a radio frequency signal spring pin, and the like disposed in the radio frequency signal via.

5. The FPC-based multichannel radio frequency connector according to claim 1, wherein the FPC flexible flat cable comprises three metal film layers and two dielectric substrate layers respectively sandwiched between the three metal film layers, and a gold finger is provided at the end of the FPC flexible flat cable.

6. The FPC-based multichannel rf connector of claim 5, wherein the metal film layers on the upper and lower surfaces of the FPC flexible flat cable are metal grounds, and the middle metal film layer is an rf signal transmission layer and is provided with a plurality of rf signal paths.

7. The FPC-based multichannel rf connector of claim 6, wherein adjacent rf signal paths are equally spaced with an array of metallized vias for signal shielding between adjacent rf signal paths.

8. The FPC-based multichannel radio frequency connector according to claim 1, wherein the FPC flexible flat cable is connected in parallel to the mounting surface of the opposite-end connection member through a radio frequency signal pin and a ground pin, or the FPC flexible flat cable is connected vertically to the mounting surface of the opposite-end connection member through a radio frequency signal pin and a ground pin.

9. The FPC-based multichannel radio frequency connector of claim 1, further comprising a metal shield cover disposed over the gold fingers and the metal structural members of the FPC flexible flat cable and configured with shield isolation ribs for signal isolation between adjacent radio frequency signal channels of the FPC gold fingers.

10. The FPC-based multichannel radio frequency connector according to claim 1, further comprising positioning pins and fastening structures configured for positioning and connection of the metallic structural member with the opposite connection member and/or the FPC flexible flat cable.