FPC loop antenna

Abstract

The invention provides an FPC loop antenna which is characterized in that the FPC loop antenna is used for an NFC ring and comprises a flexible base material, an insulating film and a copper layer conduction band; the copper layer conduction bands are distributed on the front face and the back face of the flexible base material, and interlayer conduction is achieved through electroplating through holes. The insulating film covers the front and back surfaces of the flexible base material and covers the copper layer conduction band; and the FPC loop antenna is arranged in the NFC ring in an ending welding manner. An electromagnetic field vertically penetrating through the NFC ring can be formed after head-to-tail welding, the RFID reading efficiency is improved, and meanwhile the production efficiency of the NFC ring is improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of near field communication equipment, and in particular to an FPC loop antenna. Background Art

[0002] NFC (Near Field Communication) technology has been widely used in current production and life. NFC ring products have become a popular product using NFC technology due to their practicality and portability.

[0003] Currently, conventional NFC rings use hollow coils wound with copper wire, which are then connected to a COB (Chip-on-Board) or DFN (Dual Flat No-lead Package) module made with an RFID (Radio Frequency Identification) chip via soldering. This process is lengthy and cannot be directly tuned. Rings of different finger sizes (US standard 6# to 13#) require different wire diameters, coil counts, and other parameters to achieve the standard frequency of corresponding RFID HF protocols (such as ISO14443A and ISO15693). Summary of the Invention

[0004] The embodiments of the present disclosure at least provide an FPC loop antenna, which can form an electromagnetic field vertically penetrating the NFC ring after end-to-end welding, thereby improving the RFID reading efficiency and the production efficiency of the NFC ring.

[0005] The present disclosure provides an FPC loop antenna for an NFC ring, comprising a flexible substrate, an insulating film, and a copper layer conductive tape;

[0006] The copper layer conductive strips are distributed on the front and back sides of the flexible substrate, and interlayer conduction is achieved through electroplated through-holes; the insulating film covers the front and back sides of the flexible substrate and covers the copper layer conductive strips;

[0007] The tail of the FPC loop antenna is soldered in the NFC ring.

[0008] In some embodiments, the length of the FPC loop antenna is 65.5 mm or 75.5 mm.

[0009] In some embodiments, the copper layer conductor tape has a thickness of 1.5 or 2.0 oz, and is electroplated with a nickel-gold layer having a thickness of 1-2 μ”.

[0010] In some embodiments, the single-side line spacing of the copper layer conductive strip is greater than twice the line width.

[0011] In some embodiments, the width of the FPC loop antenna is 5 mm.

[0012] In some embodiments, the FPC loop antenna is provided with a long end welding position and a short end welding position, and both the long end welding position and the short end welding position are provided with a plated through hole with a diameter of 0.15 mm. The plated through hole is connected to the plated through hole and the spacing between the plated through holes of the same copper layer conductive strip is 1 mm.

[0013] In some embodiments, the insulating film on the short end welding position of the FPC loop antenna is provided with a pad window with a length of 2 mm; the pad windows at adjacent short end welding positions are staggered and have a step difference of 0.5 mm.

[0014] In some embodiments, the FPC loop antenna is provided with a chip connection position and an independent capacitor welding position, and the independent capacitor welding position adjusts the resonant frequency to 13.56±0.5MHz through a parallel capacitor; the chip link is provided with a solder pad window on the insulating film on the independent capacitor welding position.

[0015] The present disclosure also provides a method for manufacturing an NFC ring, wherein the NFC ring includes the FPC loop antenna according to any one of the above embodiments, and the method includes:

[0016] Bend the FPC loop antenna and insert it into the inner groove of the ring;

[0017] By welding, the FPC loop antenna is closed from end to end to form a loop;

[0018] A chip and capacitor are placed on the FPC loop antenna.

[0019] In some embodiments, the method is applicable to the wafer-shaped wire bonding of the antenna for RFID high-frequency chips and the SMT patch of DFN modules; the wafer-shaped wires include gold wires, alloy wires, and aluminum wires.

[0020] In order to make the above-mentioned objectives, features and advantages of the present disclosure more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. The drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present disclosure and, together with the specification, are used to illustrate the technical solutions of the present disclosure. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without inventive effort.

[0022] Figure 1 A schematic diagram of an FPC loop antenna provided by an embodiment of the present disclosure is shown;

[0023] Figure 2 A front view schematic diagram of an FPC loop antenna provided by an embodiment of the present disclosure is shown;

[0024] Figure 3 A schematic back view of an FPC loop antenna provided by an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. The components of the embodiments of the present disclosure generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present disclosure provided in the drawings is not intended to limit the scope of the disclosure for which protection is sought, but merely represents selected embodiments of the present disclosure. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present disclosure.

[0026] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0027] The term "and / or" herein simply describes an association relationship, indicating that three relationships can exist. For example, A and / or B can represent the existence of A alone, the simultaneous existence of A and B, and the existence of B alone. In addition, the term "at least one" herein refers to any combination of at least two of any one or more of a plurality of items. For example, "at least one of A, B, and C" can represent any one or more elements selected from the set consisting of A, B, and C.

[0028] Based on the above research, the present disclosure provides an FPC loop antenna, utilizing.

[0029] like Figure 1 As shown, Figure 1 A schematic diagram of an FPC loop antenna provided in an embodiment of the present disclosure, used in an NFC ring, comprising a flexible substrate, an insulating film, and a copper conductive tape;

[0030] The copper layer conductive strips are distributed on the front and back sides of the flexible substrate, and interlayer conduction is achieved through electroplated through-holes; the insulating film covers the front and back sides of the flexible substrate and covers the copper layer conductive strips;

[0031] The tail of the FPC loop antenna is soldered in the NFC ring.

[0032] The FPC loop antenna provided by the present invention is convenient for later bending and assembly in the ring. The material with moderate bending flexibility and ensuring the best quality factor, self-resonant frequency and inductance of the antenna is selected. The copper layer conductive tape is distributed on the front and back of the flexible substrate. In order to meet different circuit requirements, the following are provided: Figure 2 The four front copper layer conduction strip distribution methods shown and Figure 3 There are two types of back copper layer conductive strip distribution methods for selection, with a total of 8 combinations.

[0033] In some embodiments, the length of the FPC loop antenna is 65.5 mm or 75.5 mm.

[0034] Since the main application scenario of the FPC loop antenna provided in the present disclosure is NFC rings, the two sizes of 65.5mm and 75.5mm can be used for American standard ring sizes 6# to 13#.

[0035] In some embodiments, the copper layer conductor tape has a thickness of 1.5 or 2.0 oz, and is electroplated with a nickel-gold layer having a thickness of 1-2 μ”.

[0036] Specifically, the copper layer conductive tape can be made of electrolytic copper or rolled copper. Electroplating the nickel-gold layer on the surface of the copper layer conductive tape takes into account the dual mass production operability of IC gold wire bonding and SMT iron sheet as well as the oxidation protection of the copper layer conductive tape.

[0037] In some embodiments, the single-side line spacing of the copper layer conductive strip is greater than twice the line width.

[0038] Specifically, the self-resonance frequency is increased to be much larger than 45 MHz by making the single-side line spacing greater than twice the line width, so as to reduce the signal loss caused by the skin effect.

[0039] In some embodiments, the width of the FPC loop antenna is 5 mm.

[0040] Specifically, in order to adapt to the different distribution methods of copper layer conductive strips, the width of the FPC loop antenna is designed with a redundant width of 5mm, which not only meets the width requirements of the NFC ring, but also ensures the overall circuit design of the FPC loop antenna.

[0041] In some embodiments, the FPC loop antenna is provided with a long end welding position and a short end welding position, and both the long end welding position and the short end welding position are provided with a plated through hole with a diameter of 0.15 mm. The plated through hole is connected to the plated through hole and the spacing between the plated through holes of the same copper layer conductive strip is 1 mm.

[0042] The insulating film on the short end welding position of the FPC loop antenna is provided with a pad window with a length of 2mm; the pad windows at adjacent short end welding positions are staggered and the step difference is 0.5mm.

[0043] Specifically, the plated through-holes are not plugged, allowing for later soldering by applying solder paste and then heating, improving production convenience. Staggered soldering windows at the short end soldering pads are used to prevent foolish soldering. This ensures that the FPC loop antenna's head and tail overlap with the correct amount of solder, preventing short circuits within the antenna.

[0044] In some embodiments, the FPC loop antenna is provided with a chip connection position and an independent capacitor welding position, and the independent capacitor welding position adjusts the resonant frequency to 13.56±0.5MHz through a parallel capacitor; the chip link is provided with a solder pad window on the insulating film on the independent capacitor welding position.

[0045] Specifically, in traditional NFC rings, it is necessary to adjust parameters such as line width and number of turns to ensure that the antennas of NFC rings of different radii reach the standard frequency of 13.56±0.5MHz. The FPC loop antenna provided in the present disclosure can achieve antenna frequency modulation by connecting capacitors of different specifications in parallel at independent capacitor welding positions to adapt to NFC rings of different finger sizes.

[0046] The present disclosure also provides a method for manufacturing an NFC ring, wherein the NFC ring includes any one of the FPC loop antennas in the above-mentioned embodiments, and the method includes:

[0047] Bend the FPC loop antenna and insert it into the inner groove of the ring;

[0048] By welding, the FPC loop antenna is closed from end to end to form a loop;

[0049] A chip and capacitor are placed on the FPC loop antenna.

[0050] In some embodiments, the method is applicable to the wafer-shaped wire bonding of the antenna for RFID high-frequency chips and the SMT patch of DFN modules; the wafer-shaped wires include gold wires, alloy wires, and aluminum wires.

[0051] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems and devices described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. In the several embodiments provided in the present disclosure, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0052] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0053] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present disclosure, which are used to illustrate the technical solutions of the present disclosure, rather than to limit them. The scope of protection of the present disclosure is not limited thereto. Although the present disclosure has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed in the present disclosure, or replace some of the technical features therein with equivalents. Such modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure, and should be included in the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure shall be subject to the scope of protection of the claims.

Claims

1. An FPC loop antenna, characterized in that: For NFC ring, including flexible substrate, insulating film and copper layer conductive tape; The copper layer conductive strips are distributed on the front and back surfaces of the flexible substrate, and interlayer conduction is achieved through electroplated through-holes; the insulating film covers the front and back surfaces of the flexible substrate and covers the copper layer conductive strips; The FPC loop antenna is welded at the end and arranged in the NFC ring.

2. The FPC loop antenna according to claim 1, wherein: The length of the FPC loop antenna is 65.5 mm or 75.5 mm.

3. The FPC loop antenna according to claim 1, wherein: The copper layer conductor tape has a thickness of 1.5 or 2.0 oz, and the surface is electroplated with a nickel-gold layer with a thickness of 1-2 μ”.

4. The FPC loop antenna according to claim 1, wherein: The single-sided line spacing of the copper layer conductive strip is greater than twice the line width.

5. The FPC loop antenna according to claim 1, wherein: The width of the FPC loop antenna is 5 mm.

6. The FPC loop antenna according to claim 1, wherein: The FPC loop antenna is provided with a long end welding position and a short end welding position, both of which are provided with a plated through hole with a diameter of 0.15 mm, and the plated through holes are connected in the plated through holes and the spacing between the plated through holes of the same copper layer conductive strip is 1 mm.

7. The FPC loop antenna according to claim 6, wherein: The insulating film on the short end welding position of the FPC loop antenna is provided with a welding pad window with a length of 2 mm; the welding pad windows at adjacent short end welding positions are staggered and have a step difference of 0.5 mm.

8. The FPC loop antenna according to claim 1, wherein: The FPC loop antenna is provided with a chip connection position and an independent capacitor welding position, and the independent capacitor welding position adjusts the resonant frequency to 13.56±0.5MHz through a parallel capacitor; the chip link is provided with a pad window on the insulating film on the independent capacitor welding position.

9. A method for manufacturing an NFC ring, characterized in that: The NFC ring includes the FPC loop antenna according to any one of claims 1 to 7, and the method includes: Bend the FPC loop antenna and insert it into the inner groove of the ring; By welding, the FPC loop antenna is closed from end to end to form a loop; A chip and capacitor are placed on the FPC loop antenna.

10. The method according to claim 9, wherein The method is applicable to the wafer-shaped wire binding of the antenna suitable for RFID high-frequency chips and the SMT patch of the DFN module; the wafer-shaped wire includes gold wire, alloy wire and aluminum wire.

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