Circuit board structure of acceleration gyroscope

Abstract

The utility model discloses a circuit board structure of an acceleration gyroscope, which comprises patch device bonding pads arranged on a circuit board, the patch device bonding pads comprise non-empty bonding pads and empty network bonding pads, and each non-empty bonding pad leads out a non-empty network wire; the empty network bonding pads comprise first empty network bonding pads and second empty network bonding pads, an empty network wire is led out from each first empty network bonding pad, a wire is not led out from each second empty network bonding pad, and the second empty network bonding pads are arranged in the patch device bonding pad in a central symmetry mode. According to the utility model, the wires are led out of the first empty network bonding pad, and the patch device bonding pad without the wires led out is in central symmetry, and the patch device bonding pad with the wires led out is in central symmetry, so that the thickness of solder paste at each part of the acceleration gyroscope is consistent, and optimization is carried out from the welding angle; weight balance of the bonding pad and the acceleration gyroscope on the circuit board can be realized, patch offset caused by unstable gravity center is reduced, and the acceleration gyroscope can provide more accurate position and direction information.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit board design, and more specifically to a circuit board structure of an acceleration gyroscope. Background Art

[0002] The gyroscope and accelerometer are two important sensors in mobile phones, playing a critical role. The gyroscope detects and measures the phone's rotation and orientation. It helps the phone determine whether the user is using the phone in landscape or portrait orientation, automatically rotating the screen to suit the user's needs. Gyroscopes also enable applications related to rotation and orientation, such as virtual reality experiences and spatial navigation in games. The accelerometer, on the other hand, measures the phone's acceleration, velocity, and orientation. It senses the phone's movement and provides accurate location information. When users perform gestures on their phones, the accelerometer tracks and interprets these gestures, translating them into corresponding actions or commands. Furthermore, the accelerometer enables motion-sensing applications such as pedometers, health monitoring, and sports games. In summary, the gyroscope and accelerometer play a crucial role in mobile phones. They enable features such as screen rotation, orientation sensing, gesture control, and motion sensing, providing users with a more convenient and intelligent mobile experience. Gyroscope and accelerometer data are important because they are key to the accuracy of movement in robotics and mobile devices, their role in positioning systems, and the formation of inertial navigation units (IMUs).

[0003] Gyroscopes and accelerometers, as inertial sensors, play a crucial role in robotics. They significantly impact the precision of robotic movement and meet the demands of accuracy, size, and temperature range, making them ideal for robotic applications. In robotics, gyroscopes track device rotation by measuring angular velocity, providing accurate posture information. Accelerometers measure acceleration—the rate of change of velocity—and estimate device velocity and displacement through integration. The combined use of these two sensors can significantly improve the precision and autonomy of robotic movement.

[0004] Gyroscopes and accelerometers also play a crucial role in mobile devices such as smartphones and tablets. They are integrated into these devices to detect motion and orientation. Accelerometers estimate the device's tilt and rotation by measuring acceleration along three axes, while gyroscopes measure the device's angular velocity and track its rotation. Fusion of these two sensor data provides more comprehensive and accurate position and orientation information, supporting a variety of applications such as step counting, indoor navigation, and motion recognition.

[0005] However, existing accelerometers are equipped with pads with empty networks and pads with network signals (pads with empty networks are pads on the device that are not assigned network signals and will not generate signal connections). Pads with network signals will lead out wiring for processing and soldering, while pads with empty networks do not lead out wiring. The pads with empty networks without lead out wiring do not lead out wiring and do not require solder paste to be applied, while pads with network signals will be applied during processing. The accelerometer is relatively light at the pads with empty networks, so the accelerometer is prone to slight offset or tilt (i.e., "sticking crookedly") at the pads with empty networks during mounting. This offset can affect the precise installation of the accelerometer, thereby reducing the accuracy of the position and direction information it provides. Utility Model Content

[0006] In order to overcome the problem that the existing acceleration gyroscope is relatively light at the empty network disk, the acceleration gyroscope is prone to slight offset or tilt at the empty pad position when the chip is mounted, and this offset will affect the precise installation of the acceleration gyroscope, thereby reducing the accuracy of the position and direction information it provides. The utility model provides a circuit board structure for an acceleration gyroscope.

[0007] The technical solution of this utility model is as follows:

[0008] A circuit board structure of an acceleration gyroscope includes a plurality of surface mount device pads arranged on the circuit board, wherein the surface mount device pads include:

[0009] Non-empty pads, each of which leads to a non-empty network trace;

[0010] Empty network pads, the empty network pads include a first empty network pad and a second empty network pad, each of the first empty network pads leads to an empty network trace, the second empty network pads do not lead to a trace, and the second empty network pads are centrally symmetrically arranged in the patch device pad.

[0011] According to the above-mentioned solution of the present invention, the width of the non-empty network trace is consistent with the width of the non-empty pad.

[0012] According to the above solution of the present invention, the width of the empty network routing line is consistent with the width of the first empty network pad.

[0013] According to the above solution of the present invention, a fan-out via is provided on the non-empty network trace, and the aperture of the fan-out via is greater than 0.1 mm.

[0014] According to the above solution of the present invention, a via pad is provided outside the fan-out via, and the diameter of the via pad is greater than 0.25 mm.

[0015] According to the above solution of the present invention, the distance between the via pad and the SMD device pad is not less than 0.2 mm.

[0016] According to the above solution of the present invention, the size of the solder pad of the patch device is 0.3 mm×0.55 mm.

[0017] According to the above solution of the present invention, a steel mesh is provided in the soldering pad of the patch device.

[0018] According to the above solution of the present invention, the size of the steel mesh is 0.25mm×0.45mm.

[0019] According to the above solution of the present invention, a solder resist window is opened outside the patch device pad, and the distance between the solder resist window and the patch device pad is not less than 0.05 mm.

[0020] The beneficial effect of the utility model according to the above scheme is that the utility model leads the first empty network pad to a routing, and makes the pads of the patch device without a routing lead-out center symmetrical, and the pads of the patch device with a routing lead-out center symmetrical, so that the copper foil thickness and solder paste thickness of the acceleration gyroscope are consistent at all places, and optimization is performed from the perspective of welding, which helps to achieve weight balance of the pads and the acceleration gyroscope on the circuit board, reduce the patch offset caused by unstable center of gravity, and the acceleration gyroscope can provide more accurate position and direction information. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic structural diagram of embodiment 1 of the present utility model;

[0022] Figure 2 This is a structural diagram of embodiment 2 of the present utility model.

[0023] In the drawings, the reference numerals are as follows:

[0024] 100. Circuit board; 10. Non-empty pad; 11. Non-empty network trace; 12. Fan-out via; 13. Via pad; 20. Empty network pad; 21. First empty network pad; 22. Second empty network pad; 23. Empty network trace; 30. Steel mesh; 40. Solder mask window. DETAILED DESCRIPTION

[0025] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0026] It should be noted that the terms "including" and "having," as well as any variations thereof, in the specification and claims of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to the process, method, product, or device. Terms such as "disposed" should be interpreted broadly, for example, and may refer to fixed connections, detachable connections, or integration; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, internal connections between two elements, or interactions between two elements, unless otherwise expressly defined. Terms such as "upper," "lower," "left," "right," "front," "back," and "bottom" indicate directions or positions based on those shown in the accompanying drawings. These are for ease of description only and should not be construed as limitations on the present invention.

[0027] It should be noted that existing accelerometers are equipped with disks with empty networks and pads with network signals (disks with empty networks are disks on the device disk that are not assigned network signals and will not generate signal connections). Disks with network signals will lead out wiring for processing and soldering, while disks with empty networks will not lead out wiring. The disks with empty networks without wiring do not lead out wiring and do not need to be paved with solder paste because no wiring will be led out. Disks with network signals will be paved with solder paste during processing. The accelerometer is relatively light at the disks with empty networks. When the accelerometer is mounted, it is easy for the accelerometer to have a slight offset or tilt (i.e., "stick crooked") at the position of the empty pads. This offset will affect the precise installation of the accelerometer, thereby reducing the accuracy of the position and direction information it provides.

[0028] like Figure 1-Figure 2 As shown, this embodiment provides a circuit board structure of an acceleration gyroscope, in which the first empty network pad 21 is led out for routing, and the pads of the patch device without routing are symmetrical in center, and the pads of the patch device with routing are symmetrical in center, so that the copper foil thickness and solder paste thickness of each part of the acceleration gyroscope are consistent, which is optimized from the perspective of welding, helps to achieve weight balance between the pad and the acceleration gyroscope on the circuit board 100, reduces the patch offset caused by unstable center of gravity, and the acceleration gyroscope can provide more accurate position and direction information.

[0029] Specifically, it includes several SMD device pads arranged on the circuit board 100, and the SMD device pads include non-empty pads 10 and empty network pads 20, and each non-empty pad 10 leads to a non-empty network trace 11; the empty network pads 20 include a first empty network pad 21 and a second empty network pad 22, each first empty network pad 21 leads to an empty network trace 23, and the second empty network pad 22 does not lead to a trace, and the second empty network pad 22 is centrally symmetrically arranged in the SMD device pads, and the non-empty pads 10 leading to the non-empty network trace 11 and the first empty network pads 21 leading to the empty network trace 23 are centrally symmetrical, that is, the SMD device pads leading to the traces are centrally symmetrical, which helps to balance the weight of the accelerometer and reduce the patch offset problem caused by the offset of the center of gravity.

[0030] For pads that require electrical connection (non-empty pads 10 and first empty network pads 21 ), a centrosymmetric layout helps reduce the asymmetry of the signal path, lowers the possibility of signal reflection and crosstalk, and improves signal integrity.

[0031] It should be noted that the arrangement of the second empty network pads 22 has a certain degree of flexibility. According to the specific pin configuration and requirements of the accelerometer gyroscope chip, the second empty network pads 22 can be flexibly arranged or omitted.

[0032] In one embodiment, the width of the non-empty network traces 11 is consistent with the width of the non-empty pads 10, helping to reduce impedance discontinuities during signal transmission, thereby reducing signal reflections and attenuation, and improving the integrity and stability of signal transmission. This consistent width also strengthens the connection between the pads and traces, reducing the risk of fracture due to stress concentration, and improving the overall reliability of the circuit board 100.

[0033] Fan-out vias 12 are provided on non-empty network traces 11. These vias are used to guide non-empty network traces 11 from one layer of the circuit board 100 to another while maintaining signal continuity and integrity. The diameter of fan-out vias 12 is greater than 0.1 mm. This larger diameter helps reduce via resistance and inductance, improves signal transmission efficiency, and mitigates manufacturing issues that may arise from an overly small aperture (such as excessive drilling precision requirements).

[0034] A via pad 13 is provided outside the fan-out via 12. The diameter of the via pad 13 is greater than 0.25 mm. The larger diameter of the via pad 13 provides a more stable connection point, which helps to enhance the adhesion between the via and the copper foil between the layers of the circuit board 100 and reduce the risk of falling off due to thermal stress or mechanical stress.

[0035] The distance between the via pad 13 and the SMD pad is not less than 0.2 mm. The 0.2 mm distance is to avoid short circuit or interference between the pads due to the expansion of the heat-affected zone during the welding process.

[0036] In one embodiment, the width of the empty network trace 23 is consistent with the width of the first empty network pad 21. The empty network trace 23 does not directly participate in the electrical connection, but maintaining its width consistent with the first empty network pad 21 helps improve the overall aesthetics and design consistency of the circuit board 100.

[0037] In one embodiment, the SMD device pads measure 0.3mm x 0.55mm, precisely accommodating most miniaturized, high-precision accelerometers and gyroscopes, ensuring soldering accuracy and stability. Within the limited space of circuit board 100, a reasonable pad size design helps optimize component layout, improving the integration and overall performance of circuit board 100.

[0038] A stencil 30 is placed inside the SMD pad, and its dimensions are 0.25mm x 0.45mm. The stencil 30 is slightly smaller than the pad, which helps prevent solder paste from overflowing outside the pad during soldering while ensuring sufficient solder paste inside the pad to form a good solder joint.

[0039] A solder mask window 40 is provided outside the SMD pads. The distance between the solder mask window 40 and the SMD pads is no less than 0.05 mm. The solder mask window 40 is a non-conductive area on the circuit board 100 that exposes the pads for soldering. Maintaining a certain distance (no less than 0.05 mm) between the solder mask window 40 and the pads prevents solder paste or solder from overflowing during soldering and bridging adjacent pads, thereby avoiding short circuits.

[0040] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all such improvements and changes should fall within the scope of protection of the claims attached to this utility model.

[0041] The above is an exemplary description of the present utility model patent in conjunction with the accompanying drawings. It is obvious that the implementation of the present utility model patent is not limited to the above-mentioned method. As long as various improvements are made using the method concept and technical solution of the present utility model patent, or the concept and technical solution of the present utility model patent are directly applied to other occasions without improvement, they are all within the scope of protection of the present utility model.

Claims

1. A circuit board structure of an acceleration gyroscope, characterized in that: The device comprises a plurality of surface mount device pads arranged on a circuit board, wherein the surface mount device pads include: Non-empty pads, each of which leads to a non-empty network trace; Empty network pads, the empty network pads include a first empty network pad and a second empty network pad, each of the first empty network pads leads to an empty network trace, the second empty network pads do not lead to a trace, and the second empty network pads are centrally symmetrically arranged in the patch device pad.

2. The circuit board structure of an acceleration gyroscope according to claim 1, characterized in that: The width of the non-empty network routing is consistent with the width of the non-empty pad.

3. The circuit board structure of an acceleration gyroscope according to claim 1, characterized in that: The width of the empty network routing line is consistent with the width of the first empty network pad.

4. The circuit board structure of an acceleration gyroscope according to claim 1 or 2, characterized in that: A fan-out via is provided on the non-empty network trace, and the aperture of the fan-out via is greater than 0.1 mm.

5. The circuit board structure of the acceleration gyroscope according to claim 4, characterized in that: A via pad is provided outside the fan-out via, and the diameter of the via pad is greater than 0.25 mm.

6. The circuit board structure of the acceleration gyroscope according to claim 5, characterized in that: The distance between the via pad and the SMD pad is not less than 0.2 mm.

7. The circuit board structure of an acceleration gyroscope according to claim 1, characterized in that: The size of the patch device pad is 0.3mm×0.55mm.

8. The circuit board structure of an acceleration gyroscope according to claim 1, characterized in that: A steel mesh is provided in the soldering pad of the patch device.

9. The circuit board structure of an acceleration gyroscope according to claim 8, characterized in that: The size of the steel mesh is 0.25 mm×0.45 mm.

10. The circuit board structure of an acceleration gyroscope according to claim 1, characterized in that: A solder resist window is provided outside the patch device pad, and a distance between the solder resist window and the patch device pad is not less than 0.05 mm.

Images