Miniaturized antenna integrated structure of low power consumption bluetooth chip

Abstract

The utility model discloses a kind of miniaturization antenna integrated structure of low-power-consumption bluetooth chip, belong to wireless communication technical field, the structure includes packaging substrate, bluetooth chip and antenna radiator, bluetooth chip is fixed on substrate top surface, antenna radiator is with serpentine structure and is located substrate bottom surface, and it is connected with the RF pin of bluetooth chip by the connecting line in via, greatly shorten radio frequency path, substrate bottom covers antenna protection glue as protection layer, via is filled with insulating material fixed circuit, the design integrates antenna in packaging interior, significantly reduce the space occupied by module, reduce signal transmission loss and external interference, improve structural mechanical strength and reliability simultaneously, especially suitable for wearable device and internet of things terminal product with harsh requirements on volume and performance.

Description

Technical Field

[0001] This utility model relates to the field of wireless communication technology, specifically a miniaturized antenna integrated structure for a low-power Bluetooth chip. Background Technology

[0002] With the rapid development of the Internet of Things (IoT) and wearable electronic devices (such as smartwatches, wireless earphones, and health monitoring patches), extremely high demands are placed on their core wireless communication modules: miniaturization, low power consumption, and high reliability. As a key component of these devices, the packaging form and connection method with the antenna of the Bluetooth Low Energy (BLE) chip directly affect the overall size and performance of the module.

[0003] In traditional designs, the Bluetooth chip and antenna are typically two separate components. The chip is soldered onto the main printed circuit board (PCB), while the antenna can take various forms, such as an inverted-F antenna (IFA), ceramic antenna, or chip antenna printed on the PCB, and is connected to the chip's radio frequency (RF) output pins via microstrip lines or transmission lines. This discrete design has several inherent drawbacks:

[0004] First, the space utilization is low. The antenna, as an independent component, occupies a large area of ​​the main PCB board and requires additional matching circuitry. This goes against the design trend of extreme miniaturization of the device and seriously restricts the flexibility of the product appearance design.

[0005] Secondly, radio frequency performance is susceptible to interference and unstable. Longer radio frequency transmission paths can introduce significant signal loss, impedance mismatch and parasitic effects, reducing radio frequency efficiency. At the same time, the dense digital lines and power modules on the motherboard are very likely to interfere with sensitive radio frequency signals, affecting communication distance and stability.

[0006] Furthermore, assembly and debugging are complex, posing challenges to reliability. The antenna's performance is highly dependent on its installation environment (i.e., the "grounding effect"), requiring complex antenna tuning after the entire unit is assembled. In addition, individual antenna components are at risk of decreased connection reliability when subjected to mechanical vibration or thermal shock.

[0007] To overcome the above problems, the industry has proposed solutions that integrate antennas with chips, such as chip-level antennas or more advanced packaged antenna technologies. However, existing integration solutions still have room for improvement in terms of further reducing package size, optimizing RF signal transmission paths, enhancing structural robustness, and simplifying manufacturing processes. Utility Model Content

[0008] In view of the above-mentioned shortcomings in the existing technology, the purpose of this utility model is to provide a miniaturized, high-performance, and highly reliable antenna structure.

[0009] The technical solution adopted by this utility model to achieve the above objectives is: a miniaturized antenna integrated structure for a low-power Bluetooth chip, including a packaging substrate and an antenna radiator. The Bluetooth chip is fixedly connected to the top surface of the packaging substrate, and the antenna radiator is fixedly connected to the bottom surface of the packaging substrate. A through hole is provided on one end of the packaging substrate corresponding to the antenna radiator. A connecting wire is fixedly connected to the antenna radiator. The connecting wire passes through the through hole and is electrically connected to the RF output pin of the Bluetooth chip.

[0010] In the above technical solution, the bottom of the packaging substrate has two sets of antenna radiators. Each set of antenna radiators on the packaging substrate has a via, and each set of antenna radiators is fixedly connected with a connecting line, which passes through the corresponding via.

[0011] The RF output pin of the Bluetooth chip is fixedly connected to a microstrip strip, and the connecting line is connected to the microstrip strip.

[0012] In the above technical solution, the antenna radiator adopts a serpentine structure.

[0013] In the above technical solution, the bottom of the packaging substrate is covered by a protective layer that is fixedly connected to the antenna radiator.

[0014] In the above technical solution, the protective layer is made of antenna protective adhesive.

[0015] In the above technical solution, the RF output pin of the Bluetooth chip is located on the side adjacent to the via.

[0016] In the above technical solution, the RF output pin of the Bluetooth chip is adjacent to the via.

[0017] The beneficial effects of this utility model are:

[0018] 1. Integrating the chip and antenna together in a single package forms a complete system-in-package, which simplifies product design, reduces the number of external components (such as eliminating the need for additional antenna matching circuits and connectors), and improves overall performance;

[0019] 2. The connecting wires are directly connected to the chip's RF pins via vias, resulting in extremely short paths. This reduces impedance mismatch, parasitic inductance, and signal transmission loss caused by longer PCB traces or coaxial cables in traditional solutions, contributing to improved RF efficiency and communication stability.

[0020] 3. The Bluetooth chip itself is located on the top of the packaging substrate, while the antenna is located at the bottom, which physically creates a certain degree of isolation and reduces the high-frequency radiation interference of the internal digital circuitry of the chip to the antenna;

[0021] 4. Using a protective layer not only physically protects the antenna, but its dielectric constant and characteristics, after selection, can also isolate external interference and tune the antenna performance;

[0022] 5. Filling the via with insulating material can fix the connecting wires, prevent them from shifting or short-circuiting, and also change the electromagnetic characteristics of the via area, which helps to reduce unnecessary radiation and signal reflection. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of this utility model;

[0024] Figure 2 for Figure 1 Detailed structural diagram of part a;

[0025] Figure 3 This is a schematic diagram of the antenna radiator in this utility model.

[0026] In the diagram: 1. Packaging substrate, 2. Bluetooth chip, 3. Antenna radiator, 4. Connecting line, 5. Microstrip, 6. Protective layer, 7. Via, 8. Insulating material. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] See Figures 1-3 This embodiment provides a miniaturized antenna integrated structure for a low-power Bluetooth chip, which mainly includes a packaging substrate 1, a Bluetooth chip 2, an antenna radiator 3, a connecting line 4, a microstrip 5, and a protective layer 6.

[0029] The packaging substrate 1 is a multilayer dielectric substrate, such as BT resin (bismaleimide triazine), FR-4 or high-frequency material (such as Rogers RO4350B). The substrate has necessary wiring layers to achieve electrical interconnection. The top surface of the packaging substrate 1 is fixedly connected to the Bluetooth chip 2 by solder balls or conductive adhesive. The Bluetooth chip 2 is a low-power system-on-a-chip that conforms to the Bluetooth standard and integrates units such as radio frequency transceiver, processor and memory.

[0030] The bottom surface of the packaging substrate 1 is fixedly connected to the antenna radiator 3 by etching, electroplating or lamination process. The antenna radiator 3 is a metal conductor, such as copper foil, and its shape is designed as a serpentine structure. This serpentine structure effectively increases the electrical length of the antenna by bending it multiple times in a limited area, so that it can resonate in the 2.4GHz Bluetooth operating frequency band, which is the key to realizing antenna miniaturization.

[0031] In this embodiment, in order to improve antenna performance, such as to achieve diversity reception or multi-mode operation, the antenna radiator 3 is provided in two sets and is symmetrically arranged on both sides of the bottom 1b of the packaging substrate 1.

[0032] A via 7 is provided on the packaging substrate 1 corresponding to the starting end of each group of antenna radiators 3. The via 7 penetrates the top and bottom surfaces of the packaging substrate 1. The position of the RF output pin of the Bluetooth chip 2 is optimized so that it is close to the corresponding via 7 side, so as to shorten the radio frequency signal transmission path to the maximum extent.

[0033] A connecting wire 4 is fixedly connected to the antenna radiator 3 by welding. The connecting wire 4 is preferably a gold wire or a copper wire. One end of the connecting wire 4 is connected to the antenna radiator 3, and the other end passes upward through the corresponding via 7. In order to lead the chip signal to the connecting wire, a microstrip 5 is fixedly connected to the RF output pin of the Bluetooth chip 2 by wire bonding. The microstrip 5 is printed on the top surface of the packaging substrate 1, and its impedance is designed to be 50 ohms to achieve impedance matching. After the connecting wire 4 passes through the via 7, its end is electrically connected to the microstrip 5 by bonding or welding, thereby feeding the radio frequency signal of the Bluetooth chip 2 to the antenna radiator 3.

[0034] The inner wall of the via 7 is metallized and electroplated. However, in order to prevent the antenna signal from short-circuiting with other circuits inside the substrate, the via 7 is filled with an insulating material 8, such as resin or epoxy plastic. The insulating material 8 covers and fixes the connecting line 4 inside, which not only plays a role in structural support and protection, but also optimizes the electromagnetic environment of the via area.

[0035] Finally, all antenna radiators 3 and part of the bottom surface are covered on the bottom of the packaging substrate 1, and a protective layer 6 is fixedly connected by dispensing or pressing. The protective layer 6 uses a special antenna protective adhesive (such as epoxy resin or polyimide adhesive), which has uniform thickness and stable dielectric constant. This protective layer 6 not only physically protects the fragile antenna traces from scratches and corrosion, but its dielectric properties are also incorporated into the antenna design to ultimately tune the resonant frequency and bandwidth of the antenna.

[0036] In summary, during assembly, firstly, a serpentine antenna radiator 3 is formed on the bottom surface 1b of the packaging substrate 1. Then, one end of the connecting wire 4 is soldered to the antenna body 3 and passed through the corresponding via 7. Next, the Bluetooth chip 2 is mounted on the top surface of the substrate and the microstrip 5 is bonded. Then, the end of the connecting wire 4 is connected to the microstrip 5. Then, insulating material 8 is injected into the via 7 and cured. Finally, antenna protective adhesive is coated or pressed onto the bottom of the substrate to form a protective layer 6, and the whole package is then performed.

[0037] In summary, the structure provided in this embodiment, by integrating the antenna and chip package into a single design, greatly saves space, optimizes radio frequency performance, and improves the reliability and ease of manufacturing of the module.

[0038] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0039] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A miniaturized antenna integrated structure for a low-power Bluetooth chip, comprising a packaging substrate (1) and an antenna radiator (3), wherein a Bluetooth chip (2) is fixedly connected to the top surface of the packaging substrate (1), characterized in that: The antenna radiator (3) is fixedly connected to the bottom surface of the packaging substrate (1). A via (7) is provided on one end of the packaging substrate (1) corresponding to the antenna radiator (3). A connecting line (4) is fixedly connected to the antenna radiator (3). The connecting line (4) passes through the via and is electrically connected to the RF output pin of the Bluetooth chip (2).

2. The miniaturized antenna integrated structure of a low-power Bluetooth chip according to claim 1, characterized in that: The bottom of the packaging substrate (1) has two sets of antenna radiators (3). Each set of antenna radiators (3) on the packaging substrate (1) has a via (7). Each set of antenna radiators (3) is fixedly connected with a connecting line (4). The connecting line (4) passes through the corresponding via (7). The RF output pin of the Bluetooth chip (2) is fixedly connected to a microstrip strip (5), and the connecting line (4) is connected to the microstrip strip (5).

3. The miniaturized antenna integrated structure of a low-power Bluetooth chip according to claim 2, characterized in that: The antenna radiator (3) adopts a serpentine structure.

4. The miniaturized antenna integrated structure of a low-power Bluetooth chip according to claim 2, characterized in that: The bottom of the encapsulation substrate (1) is covered by a protective layer (6) that is fixedly connected to the antenna radiator (3).

5. The miniaturized antenna integrated structure of a low-power Bluetooth chip according to claim 4, characterized in that: The protective layer (6) is made of antenna protective adhesive.

6. The miniaturized antenna integrated structure of a low-power Bluetooth chip according to claim 1, characterized in that: The via (7) is filled with insulating material (8), which covers the connecting wire (4).

7. The miniaturized antenna integrated structure of a low-power Bluetooth chip according to claim 1, characterized in that: The RF output pin of the Bluetooth chip (2) is located on the side adjacent to the via (7).

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