Packaging routing structure for enhancing differential signal isolation
By adding ground signal pins and pads within the package and using wire bonding with a higher arc to form multiple signal return paths, the problem of insufficient signal isolation in area-sensitive scenarios is solved, thereby reducing crosstalk between signals and improving signal quality.
Patent Information
- Application Number
- CN202520511256.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-23
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2035-03-23
AI Technical Summary
In area-sensitive or limited scenarios, traditional methods cannot effectively increase the isolation of signals within the package by adjusting signal traces or pin spacing, resulting in the inability to effectively solve crosstalk problems.
By adding ground signal pins and pads within the package and connecting them with higher arc wire bonding, multiple signal return paths are formed, enhancing the isolation between signals.
Without increasing the package area, it significantly reduces crosstalk between signals, improves signal quality, and enhances the isolation of signal transmission.
Smart Images
Figure CN223928820U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of chip packaging technology, specifically relating to a packaging wire bonding structure that enhances the isolation of differential signals. Background Technology
[0002] Isolation, also known as crosstalk, is a scattering parameter that reflects the degree of coupling between signal transmission lines on a circuit board. Poor isolation can negatively impact signal quality and even cause the system to malfunction, posing a significant threat. Therefore, in system design, it is generally desirable to have as much isolation as possible between signals, i.e., as little crosstalk as possible.
[0003] Currently, the traditional approach to address crosstalk issues within a package is to increase the spacing between signal traces or pins on the circuit board, or to wrap ground around both sides of the signal lines. The structure is as follows: Figure 1 As shown in the diagram, the two middle pins are protected critical signal pins, and the one above and one below are ground pins, which is the traditional grounding treatment. In some scenarios, this method is quite effective, but in area-sensitive or limited scenarios, it's impossible to infinitely extend the distance between signal traces or pins within the package. Utility Model Content
[0004] The purpose of this invention is to propose a packaging wire bonding structure that enhances the isolation of differential signals, in order to solve the technical problem mentioned in the background art that the isolation cannot be increased by adjusting the distance in area-sensitive or limited scenarios.
[0005] To achieve the above objectives, this utility model provides the following technical solution:
[0006] A package wire bonding structure for enhancing differential signal isolation comprises a critical signal pin assembly, a ground pin assembly, a pad assembly, and wire bonding connecting the pins and the pads. The critical signal pin assembly includes critical signal pin A and critical signal pin B. The ground pin assembly includes ground pin C located on both sides of the critical signal pin assembly, and ground pin D located between critical signal pin A and critical signal pin B. Ground pin D is not connected to the large package pad.
[0007] Furthermore, the ground pin C is connected to the package pad, and the pad assembly includes multiple pads corresponding to the critical signal pin assembly and the ground pin assembly.
[0008] Furthermore, the wire connecting the ground pin D uses a higher arc.
[0009] Another objective of this invention is to provide a different package wire bonding structure for enhancing differential signal isolation, comprising a critical signal pin assembly, a ground pin assembly, a pad assembly, and wire bonding connecting the pins and the pads. The critical signal pin assembly includes critical signal pin A and critical signal pin B. The ground pin assembly includes ground pin C located on both sides of the critical signal pin assembly, and ground pin E located between critical signal pin A and critical signal pin B. Both ground pin C and ground pin E are connected to the large package pad.
[0010] Furthermore, the pad assembly includes multiple pads corresponding to the critical signal pin assembly and the ground pin assembly.
[0011] This utility model has the following beneficial effects:
[0012] This invention proposes a wire bonding structure for a packaging framework to enhance signal isolation, reduce crosstalk, and improve signal quality. Its advantage lies in the fact that, in traditional wire bonding packaging, where the signal transmission path for high-speed signals cannot be shortened further—meaning the parasitic parameters of the circuitry cannot be reduced through physical wiring as in flip chip (FC) packaging, and the distance between signals cannot be increased—this invention's structure can, to a certain extent, reduce crosstalk, increase isolation, and thus improve signal quality. Attached Figure Description
[0013] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0014] Figure 1 A schematic diagram of the structure for land-use processing using existing technology;
[0015] Figure 2 This is a schematic diagram of the structure of Example 1;
[0016] Figure 3 This is a schematic diagram of the structure of Example 2;
[0017] Figure 4 Simulation results for a package structure without a ground pin in the middle of the signal lines;
[0018] Figure 5 Simulation results for the package structure of the ground pins between signals.
[0019] In the attached diagram, the components represented by each label are as follows:
[0020] Critical signal pin A-1, critical signal pin B-2, ground pin C-3, ground pin D-4, package pad-5, chip-6, ground pin E-7. Detailed Implementation
[0021] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0022] Example 1:
[0023] See Figure 2 As shown, a package wire bonding structure for enhancing differential signal isolation comprises a critical signal pin assembly, a ground pin assembly, a pad assembly, and wire bonding connecting the pins and the pads. The critical signal pin assembly includes critical signal pin A1 and critical signal pin B2; the ground pin assembly includes ground pins C3 respectively located on both sides of the critical signal pin assembly, and ground pin D4 located between critical signal pins A1 and B2. Ground pin C3 is connected to a large package pad 5, while ground pin D4 is not connected to the large package pad 5; the pad assembly is disposed on a chip 6 and includes multiple pads corresponding to the critical signal pin assembly and the ground pin assembly, and the pad assembly is connected to the critical signal pin assembly and the ground pin assembly via wire bonding.
[0024] This embodiment adds ground pads between the differential signal pads on the chip, and also adds a ground pin to the bottom of the corresponding package frame or substrate. These are then connected via wire bonding, without increasing the package area, which remains the same as the original structure. Only a portion of the metal in the signal connection area needs to be removed to reserve space for the added ground pads and wire bonding, without affecting the overall package size. The added pads on the chip do not occupy the area of the original pads, allowing the chip area to remain consistent with the original chip area. The added wire bonding can use a higher arc than the original wire bonding, ensuring the two arcs are not at the same height, thus greatly reducing the risk of wire contact during packaging.
[0025] Example 2 :
[0026] See Figure 3As shown, a package wire bonding structure for enhancing differential signal isolation comprises a critical signal pin assembly, a ground pin assembly, a pad assembly, and wire bonding connecting the pins and the pads. The critical signal pin assembly includes critical signal pin A1 and critical signal pin B2; the ground pin assembly includes ground pin C3 located on both sides of the critical signal pin assembly, and ground pin E7 located between critical signal pin A1 and critical signal pin B2, both ground pin C3 and ground pin E7 being connected to a large package pad 5; the pad assembly is disposed on a chip 6 and includes multiple pads corresponding to the critical signal pin assembly and the ground pin assembly, and the pad assembly is connected to the critical signal pin assembly and the ground pin assembly via wire bonding.
[0027] This embodiment uses a different structure, which also does not increase the package area. The structural difference from Embodiment 1 is that the newly added ground pin E7 is connected to the large package pad 5 in the middle. There is no need to add pins to the bottom of the package, and it can achieve full pin compatibility with the original package structure.
[0028] Both of the above-described packaging structures can increase shielding and reduce crosstalk between signals. The ground signal serves as the signal return path in the system. Adding ground pads and bonding wires increases the number of signal return paths. Originally, there were only two paths (one ground wire on each side), but now, with the addition of a ground bonding wire between the signals, the number of return paths increases to three. This reduces the parasitic parameters of the signal lines to some extent and also provides shielding, effectively reducing electromagnetic interference and electric field coupling interference, thus reducing crosstalk received by the signal and enhancing signal transmission quality.
[0029] To verify the effectiveness of the above structure, simulations were performed using existing technologies as a reference. The same attack line and the same victim line were selected to simulate and compare the crosstalk values of the encapsulation structure.
[0030] Figure 1 Simulation results of the medium-sized packaging structure are as follows Figure 4 As shown. The simulation results of the packaging structure of this utility model are as follows. Figure 5 As shown in the simulation results above, the crosstalk of the differential signal without adding a ground pin in the middle of the signal line is -72.47dB at 20GHz, while the crosstalk with adding a ground pin between the signals in this invention is -81.43dB at 20GHz. The improvement in isolation is quite significant.
[0031] This invention can maintain complete compatibility and consistency without changing the original structure and order of the signal pins in the package. By adding ground signal pins inside the package, adding ground pads on the chip, and wire bonding, it can significantly improve the isolation between signal wires in the package structure, reduce the signal integrity damage caused by crosstalk between signals, and improve the signal transmission quality in the package structure to a certain extent.
[0032] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it.
Claims
1. A wire bonding structure for enhancing differential signal isolation, characterized in that, It consists of a key signal pin assembly, a ground pin assembly, a pad assembly, and wire bonding connecting the pins and the pads. The key signal pin assembly includes a key signal pin A (1) and a key signal pin B (2). The ground pin assembly includes a ground pin C (3) located on both sides of the key signal pin assembly, and a ground pin D (4) located between the key signal pin A (1) and the key signal pin B (2). The ground pin D (4) is not connected to the large package pad (5).
2. The packaging wire bonding structure for enhancing differential signal isolation according to claim 1, characterized in that, The ground pin C (3) is connected to the package pad (5), and the pad assembly includes multiple pads corresponding to the critical signal pin assembly and the ground pin assembly.
3. The packaging wire bonding structure for enhancing differential signal isolation according to claim 2, characterized in that, The wire connecting the ground pin D(4) uses a higher arc.
4. A wire bonding structure for enhancing differential signal isolation, characterized in that, It consists of a critical signal pin assembly, a ground pin assembly, a pad assembly, and wire bonding connecting the pins and the pads. The critical signal pin assembly includes a critical signal pin A (1) and a critical signal pin B (2). The ground pin assembly includes a ground pin C (3) located on both sides of the critical signal pin assembly, and a ground pin E (7) located between the critical signal pin A (1) and the critical signal pin B (2). Both the ground pin C (3) and the ground pin E (7) are connected to the large package pad (5).
5. The packaging wire bonding structure for enhancing differential signal isolation according to claim 4, characterized in that, The pad assembly includes multiple pads corresponding to the critical signal pin assembly and the ground pin assembly.