Improving the passive bandwidth structure of bowtie probes
By introducing a return shroud into the butterfly detector, the impedance at the Bding gold wire is reduced, and the impedance matching is optimized, thus solving the problem of insufficient passive bandwidth of traditional butterfly detectors and achieving higher signal transmission efficiency and bandwidth.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHENGDU XIJIAO JIERUI OPTOELECTRONICS TECH CO LTD
- Filing Date
- 2025-05-23
- Publication Date
- 2026-07-14
AI Technical Summary
In the passive bandwidth structure of traditional butterfly detectors, the impedance at the Bding point is high, which leads to a decrease in signal transmission quality and cannot meet the requirements of high-speed, wideband signal processing.
A return shroud is introduced into the butterfly detector structure. It is made of stainless steel and the capacitance at the Bding gold wire is increased to reduce the characteristic impedance. By optimizing the impedance matching, a clearance groove is designed at the bottom of the return shroud for assembly.
By designing the return shroud, the 3dB bandwidth was increased from 60GHz to 64.7GHz, and the insertion loss was significantly reduced within the DC-67G bandwidth range, thereby improving the passive bandwidth of the butterfly detector and enhancing signal transmission efficiency.
Smart Images
Figure CN224503657U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of butterfly detector technology, and in particular to a structure for improving the passive bandwidth of a butterfly detector. Background Technology
[0002] Currently, in fields such as optical communication and terahertz detection, butterfly detectors serve as crucial photoelectric conversion devices, and their performance plays a decisive role in the overall system performance. With the development of communication technology towards high speed and large capacity, and the increasing demand for broadband signal capture in detection technology, the requirements for the passive bandwidth of butterfly detectors are becoming increasingly stringent.
[0003] In the existing technology, when traditional butterfly detectors are patch-coupled, the connection between the substrate and various parts usually relies on binding or soldering. These connection points are usually important nodes that affect the passive bandwidth. In most passive bandwidth structures of butterfly detectors, the impedance at the binding point is high, which degrades the signal transmission quality and makes butterfly detectors unable to meet the growing demand for high-speed, wideband signal processing.
[0004] Therefore, we propose a passive bandwidth structure for improving the butterfly detector to solve the above problems. Utility Model Content
[0005] The purpose of this application is to provide a structure for improving the passive bandwidth of a butterfly detector, which has the effect of significantly improving the passive bandwidth of the butterfly detector.
[0006] The above-mentioned technical objective of this application is achieved through the following technical solution: a passive bandwidth improvement structure for a butterfly detector, comprising a substrate, a high-frequency capacitor, a Bding gold wire, a butterfly detector housing, an RF connector, and a TIA chip transimpedance amplifier. The substrate, the high-frequency capacitor, and the Bding gold wire are all fixedly connected to the top of the butterfly detector housing, the RF connector is fixedly connected to the bottom of the butterfly detector housing, the TIA chip transimpedance amplifier is fixedly connected to the top of the butterfly detector housing, and a return shroud is provided on the top of the Bding gold wire.
[0007] A further feature of this application is that the substrate is a standard 50-ohm transmission line for signal transmission.
[0008] A further feature of this application is that the high-frequency capacitor is used for signal coupling, and the TIA chip transimpedance amplifier is used to amplify the electrical signal.
[0009] A further feature of this application is that the return shroud is made of stainless steel and is used to provide a return path for high-speed signals.
[0010] A further feature of this application is that the bottom of the return shroud has an avoidance groove with one side open.
[0011] This application includes at least one of the following beneficial technical effects:
[0012] This application increases the capacitance at the bonding wire by designing the return shroud, reduces the characteristic impedance, optimizes impedance matching, and, as verified by simulation, increases the 3dB bandwidth from 60GHz to 64.7GHz, significantly reduces insertion loss within the DC-67G bandwidth range, and greatly improves the passive bandwidth of the butterfly detector. Attached Figure Description
[0013] Figure 1 This is a three-dimensional structural diagram of the passive bandwidth structure of a butterfly detector in the prior art.
[0014] Figure 2 This is a three-dimensional structural diagram of the passive bandwidth structure of the butterfly detector in this embodiment.
[0015] Figure 3 This is a three-dimensional structural diagram of the return shroud in this embodiment.
[0016] Figure 4 yes Figure 1 The impedance curve.
[0017] Figure 5 yes Figure 2 The impedance curve.
[0018] Figure 6 yes Figure 4 Import the simulation parameter curves generated in HFSS.
[0019] Figure 7 yes Figure 5 Import the simulation parameter curves generated in HFSS.
[0020] Figure 8 yes Figure 4 Simulation parameters and Figure 5 A comparison chart of simulation parameters.
[0021] In the diagram, 1 is the substrate; 2 is the high-frequency capacitor; 3 is the bonding wire; 4 is the butterfly detector housing; 5 is the RF connector; 6 is the TIA chip transimpedance amplifier; and 7 is the return shroud. Detailed Implementation
[0022] The technical solution of this application will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0023] See Figures 1-8 This application provides a structure for improving the passive bandwidth of a butterfly detector, including a substrate 1, a high-frequency capacitor 2, a bonding wire 3, a butterfly detector housing 4, an RF connector 5, and a TIA chip transimpedance amplifier 6. The substrate 1, high-frequency capacitor 2, and bonding wire 3 are all fixedly connected to the top of the butterfly detector housing 4. The RF connector 5 is fixedly connected to the bottom of the butterfly detector housing 4. The TIA chip transimpedance amplifier 6 is fixedly connected to the top of the butterfly detector housing 4. A return current shield 7 is provided on the top of the bonding wire 3, covering the bonding wire 3 to ensure good electrical conduction between the return current shield 7 and the butterfly detector housing 4. The return current shield 7 is made of stainless steel and is used to provide a return path for high-speed signals to reduce signal loss and improve signal transmission efficiency.
[0024] In this embodiment, substrate 1 is a standard 50-ohm transmission line used for signal transmission, which can effectively ensure the stability of signal transmission; high-frequency capacitor 2 is used for signal coupling to ensure the lossless passage of high-speed AC signals; through the combined action of substrate 1 and high-frequency capacitor 2, the quality of signal transmission and processing is improved; Bding gold wire 3 is used to connect substrate and RF connector to achieve reliable electrical connection and ensure smooth signal transmission path; butterfly detector housing 4 is used for protection, shielding, heat dissipation and as a signal reference layer, providing a good environment for stable operation of internal components and enhancing the overall performance and reliability of the detector; RF connector 5 is used for external connection and transmission of high-speed signals; TIA chip transimpedance amplifier 6 is used to amplify the electrical signal converted by PD, improve signal strength, and facilitate subsequent signal analysis and processing.
[0025] In this embodiment, the bottom of the return shroud 7 is provided with a clearance groove with one side open. The design of the clearance groove facilitates the assembly of the return shroud 7.
[0026] In this embodiment, according to transmission line theory, impedance mismatch is the fundamental cause affecting the bandwidth of high-speed signal transmission. Based on the impedance calculation formula... By appropriately adjusting the equivalent inductance and equivalent capacitance of the transmission line, the impedance of the transmission line can be optimized, thereby optimizing the transmission line bandwidth. Figure 4 The impedance of the existing passive bandwidth structure of the butterfly detector shown has a maximum value of 62.3Ω, which is the impedance at the three points where the gold wire is bonded. Figure 5 The impedance of the improved passive bandwidth structure of the butterfly detector shown in this paper reaches a maximum of 56.4Ω; furthermore, through... Figure 4 and Figure 5 The comparison shows that Figure 5A return shield 7 with metal shielding was added at the Bding gold wire 3, which is equivalent to increasing the capacitance at the Bding gold wire 3. According to the impedance calculation formula above, it can be seen that the characteristic impedance at this point is reduced, and the simulation results are in line with expectations. The impedance at this point is significantly reduced. According to transmission line theory, the better the impedance matching, the smaller the reflection and the larger the bandwidth.
[0027] In this embodiment, Figure 6 Importing in HFSS as shown Figure 4 The model was established with a pair of differential ports, and the simulation parameters of S21 were: 3dB bandwidth at 60GHz; Figure 7 Importing in HFSS as shown Figure 5 The model was constructed using a pair of differential ports, and the simulated S21 parameters were: 3dB bandwidth at 64.7GHz; Figure 8 As shown Figure 6 and Figure 7 By comparing the simulation results, it can be seen that within the bandwidth range of DC-67G, the S21 parameter, i.e. the insertion loss, of the optimized passive bandwidth structure of the butterfly detector is much smaller than that of the unoptimized passive bandwidth structure. Before 30G, the insertion loss is even less than half of that before optimization. This reduces the loss of the passive transmission link throughout the entire effective bandwidth range, thereby greatly improving the bandwidth of the passive transmission link.
[0028] The simulation results above show that adding the return shroud 7 can significantly improve the passive bandwidth of the butterfly detector.
[0029] With the above structure, the passive bandwidth improvement structure for the butterfly detector provided in this application increases the capacitance at the Bding gold wire 3 in the return shroud 7 during use, reduces the characteristic impedance, optimizes impedance matching, and, as verified by simulation, the 3dB bandwidth is increased from 60GHz to 64.7GHz, the insertion loss is significantly reduced in the DC-67G bandwidth range, and the passive bandwidth of the butterfly detector is greatly improved.
Claims
1. A structure for improving the passive bandwidth of a butterfly detector, characterized in that, The device includes a substrate (1), a high-frequency capacitor (2), a Bding gold wire (3), a butterfly detector housing (4), an RF connector (5), and a TIA chip transimpedance amplifier (6). The substrate (1), the high-frequency capacitor (2), and the Bding gold wire (3) are all fixedly connected to the top of the butterfly detector housing (4). The RF connector (5) is fixedly connected to the bottom of the butterfly detector housing (4). The TIA chip transimpedance amplifier (6) is fixedly connected to the top of the butterfly detector housing (4). A return shroud (7) is provided on the top of the Bding gold wire (3).
2. The structure for improving the passive bandwidth of a butterfly detector according to claim 1, characterized in that: The substrate (1) is a standard 50-ohm transmission line used for signal transmission.
3. The structure for improving the passive bandwidth of a butterfly detector according to claim 1, characterized in that: The high-frequency capacitor (2) is used for signal coupling, and the TIA chip transimpedance amplifier (6) is used to amplify the electrical signal.
4. The structure for improving the passive bandwidth of a butterfly detector according to claim 1, characterized in that: The return shield (7) is made of stainless steel and is used to provide a return path for high-speed signals.
5. The structure for improving the passive bandwidth of a butterfly detector according to claim 1, characterized in that: The bottom of the return shroud (7) is provided with a clearance groove with one side open.