Broadband bias device circuit and miniaturized broadband bias device
By designing a broadband bias circuit with 6 yuan devices, it solves the problem of difficulty in satisfying the broadband application of traditional bias, realized miniaturization and cost reduction, and is suitable for high -frequency applications such as light modules.
Patent Information
- Application Number
- CN202420565127.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-22
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-03-22
AI Technical Summary
Traditional biasers are difficult to meet broadband applications, especially in optical modules. The RF signal bandwidth is very wide, and the traditional biaser circuit is complex and large in size, which cannot achieve miniaturization and low cost.
Designed a broadband bias circuit, using 6 yuan device (first inductance, second inductance, first resistance, second resistance, first capacitor, and second capacitor), through optimization of the connection of inductance, capacitance, and resistors Methods to realize broadband choking and communicating directly, reducing the volume of bias.
While ensuring the broadband, the miniaturization and cost of the bonder are suitable for small -sized modules. The insertion loss is less than 1DB, the isolation degree is greater than 30DB, and the demand of the frequency range of 100MHz ~ 10GHz is met.
Smart Images
Figure CN222423221U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of communication equipment, in particular to a broadband bias device circuit and a miniaturized broadband bias device. Background Art
[0002] The bias device is a component in an electronic system that injects DC into the RF path. The DC injection does not affect the RF signal of the main transmission path. The bias device can be used to power active devices (such as amplifiers, diodes, etc.), or use RF cables to transmit DC and RF signals to the remote end at the same time. In the optical module, the broadband RF signal is input into the laser to modulate the optical signal. At this time, the bias device is required to drive the laser so that the laser works in a certain DC state. In some optical communication modules, the RF signal bandwidth is very wide, covering 100MHz to 8GHz. Traditional bias devices are difficult to cover such a wide passband, and broadband bias devices require multiple devices to implement, and the circuit is complex and large in size. In optical module applications, the layout space is limited, so miniaturization and broadband requirements are put forward for filters.
[0003] Conventional bias trolleys such as Figure 1 As shown, it is composed of a choke inductor, a DC blocking capacitor, and a decoupling capacitor. Due to the influence of the parasitic parallel capacitance of the inductor, self-resonance will occur at a certain frequency. After the operating frequency exceeds the self-resonant frequency of the inductor, the choke effect of the inductor gradually deteriorates, and part of the RF signal enters the DC line; similarly, due to the influence of the parasitic series inductance of the capacitor, self-resonance will occur at a certain frequency. After the operating frequency exceeds the self-resonant frequency of the capacitor, the AC direct-pass effect of the capacitor gradually deteriorates, and part of the RF signal will be reflected. Due to the above parasitic effects, the traditional bias tamper solution has a limited working bandwidth and cannot meet broadband applications.
[0004] The general solution to broadband biasing is to use a combination of multiple inductors and capacitors to achieve broadband, such as Figure 2 As shown in the figure, due to the use of multiple devices, the required layout space is large. Another broadband solution is to use a conical inductor as a choke inductor. The self-resonant frequency of the conical inductor is very high, which can achieve broadband choke. However, the price of the conical inductor is very high and it is not suitable for low-cost applications. In addition, the inductor has a large diameter and requires a large height, which is not suitable for miniaturized applications. Utility Model Content
[0005] In view of this, the utility model provides a broadband bias device circuit and a miniaturized broadband bias device, which can achieve miniaturization while ensuring broadband and reduce costs.
[0006] The technical solution adopted by the utility model is as follows:
[0007] A broadband bias circuit includes a first inductor, a second inductor, a first resistor, a second resistor, a first capacitor and a second capacitor;
[0008] One end of the first inductor and the first capacitor are both connected to the external RF+DC port electrode, the other end of the first capacitor is connected to the external RF port electrode, the other end of the first inductor is connected to the second inductor, and the other end of the second inductor is connected to the external DC port electrode; one end of the second capacitor is connected to the DC port, and the other end of the second capacitor is connected to the external ground electrode; both ends of the first resistor are connected in parallel with the first inductor, and both ends of the second resistor are connected in parallel with the second inductor.
[0009] The utility model also provides a miniaturized broadband bias device, comprising the above-mentioned broadband bias device circuit, a substrate and a shielding cover;
[0010] The bottom surface of the substrate is a bias electrode, which is divided into an RF+DC port electrode, an RF port electrode, a DC port electrode and a ground electrode; the top surface of the substrate fixes the broadband bias circuit; the shielding cover is fixed to the top surface of the substrate to encapsulate the broadband bias circuit.
[0011] Furthermore, the line connecting the RF+DC port electrode and the RF port electrode is parallel to the substrate frame, the RF+DC port electrode is spaced a set distance from the ground electrode, the RF port electrode is spaced a set distance from the ground electrode, and the DC port electrode is spaced a set distance from the ground electrode.
[0012] Furthermore, the sizes of the RF+DC port electrode and the RF port electrode are both 0.5mm×0.3mm, and the intervals between the RF+DC port electrode and the RF port electrode and the ground electrode are 0.2mm; the size of the DC port electrode is 0.6mm×0.6mm, and the interval between the DC port electrode and the ground electrode is 0.3mm.
[0013] Furthermore, the connection direction of the two electrodes in the first capacitor is parallel to the connection direction of the RF+DC port electrode and the RF port electrode; the connection direction of the two electrodes in the first inductor is perpendicular to the connection direction of the RF+DC port electrode and the RF port electrode; the connection direction of the two ends of the first resistor is perpendicular to the connection direction of the RF+DC port electrode and the RF port electrode; and the end of the second capacitor connected to the ground electrode is no more than 1 mm away from the grounding hole.
[0014] Furthermore, the connection direction of the two electrodes in the second inductor is parallel to the connection direction of the RF+DC port electrode and the RF port electrode; the interval range between the second inductor and the second resistor is 0.2 to 1 mm, and the interval range between the first inductor and the first resistor is 0.2 to 1 mm.
[0015] Beneficial effects:
[0016] 1. The utility model simplifies the composition of broadband bias device components, and can achieve broadband with only 6 components. It has a smaller size and can be applied to small-size modules, so that the bias device can be miniaturized and the cost can be reduced.
[0017] 2. The layout of the RF+DC port electrode, RF port electrode, DC port electrode and ground electrode of the utility model enables the components to be compactly mounted on the upper surface of the substrate and connected to the bottom electrode of the substrate, thereby reducing the volume of the bias device.
[0018] 3. The connection direction of the two electrodes in the second inductor of the utility model is parallel to the connection direction of the RF+DC port electrode and the RF port electrode, which can further reduce the volume of the bias device. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 This is a schematic diagram of the traditional bias circuit principle.
[0020] Figure 2 This is a schematic diagram of the principle of a traditional broadband bias tee circuit.
[0021] Figure 3 This is a schematic diagram of the bias circuit principle of the utility model.
[0022] Figure 4 It is a schematic diagram of the three-dimensional structure of the bias device of the utility model.
[0023] Figure 5 It is a schematic diagram of the bottom surface of the bias device substrate of the utility model.
[0024] Figure 6 It is a schematic diagram of the top surface of the bias device substrate of the utility model.
[0025] Figure 7 This is a schematic diagram of the installation of the bias device substrate and components of the utility model.
[0026] Figure 8 Insertion loss curve of the bias tee of the embodiment.
[0027] Fig. 9 FIG. 4 is a return loss curve of the bias tee of the embodiment.
[0028] Fig.10 2 is a bias breaker isolation curve of an embodiment.
[0029] Among them, 1-components, 2-shielding cover, 3-substrate, 4-grounding hole. DETAILED DESCRIPTION
[0030] The present invention is described in detail below with reference to the accompanying drawings and embodiments.
[0031] The utility model provides a broadband bias circuit, such as Figure 3 As shown, it includes a first inductor L1, a second inductor L2, a first resistor R1, a second resistor R2, a first capacitor C1 and a second capacitor C2.
[0032] One end of the first inductor L1 and the first capacitor C1 are both connected to the external RF+DC port electrode, and the other end of the first capacitor C1 is connected to the external RF port electrode; the other end of the first inductor L1 is connected to the second inductor L2, the other end of the second inductor L2 is connected to the external DC port electrode, one end of the second capacitor C2 is connected to the DC port, and the other end of the second capacitor C2 is connected to the external ground electrode; both ends of the first resistor R1 are connected in parallel with the first inductor L1, and both ends of the second resistor R2 are connected in parallel with the second inductor L2.
[0033] The utility model also provides a miniaturized broadband bias device, such as Figure 4 As shown, it includes the above-mentioned broadband bias circuit, substrate 3 and shielding cover 2.
[0034] The bottom surface of the substrate 3 is the bias electrode, which is divided into RF+DC port electrode, RF port electrode, DC port electrode and ground electrode. The top surface (upper surface) of the substrate 3 is fixed with the broadband bias circuit, that is, the first inductor L1, the second inductor L2, the first resistor R1, the second resistor R2, the first capacitor C1 and the second capacitor C2. These components 1 are fixed on the upper surface of the substrate 3 by soldering or glue. The shielding cover 2 is a hollow open box-shaped structure, which is buckled on the upper surface of the substrate 3 with the opening facing downward, and is fixed to the substrate 3 by soldering or glue, and the broadband bias circuit is encapsulated inside. The shielding cover 2 is made of metal, plastic or other materials.
[0035] like Figure 5 The bottom surface of the substrate 3 shown, the connection line of the RF+DC port electrode and the RF port electrode is parallel to the frame of the substrate 3, and the RF+DC port electrode and the RF port electrode are located at the two ends of the lower part of the substrate 3; the RF+DC port electrode and the ground electrode are separated by a set distance, and the RF port electrode and the ground electrode are separated by a set distance; the DC port electrode is located at the upper right corner of the substrate 3, and the DC port electrode and the ground electrode are separated by a set distance. The areas outside the RF port electrode, the RF+DC port electrode, and the DC port electrode are all ground electrodes. The shapes of the RF port electrode, the RF+DC port electrode, and the DC port electrode can be circular, square, rectangular, or other combined structural shapes.
[0036] In this embodiment, the shapes of the RF+DC port electrode and the RF port electrode are both a combination of a semicircular arc and a rectangular structure, the semicircular arc is tangent to the two straight sides of the rectangle, the size of the rectangle is 0.5mm×0.3mm, and the diameter of the semicircular arc is 0.3mm; the RF+DC port electrode, the RF port electrode and the ground electrode are all spaced 0.2mm apart; the DC port electrode is a square with a size of 0.6mm×0.6mm, and the DC port electrode is spaced 0.3mm apart from the ground electrode.
[0037] like Figure 6 , Figure 7 As shown, the connection direction of the two electrodes in the first capacitor C1 is parallel to the connection direction of the RF+DC port electrode and the RF port electrode; the connection direction of the two electrodes in the first inductor L1 is perpendicular to the connection direction of the RF+DC port electrode and the RF port electrode; the connection direction of the two ends of the first resistor R1 is perpendicular to the connection direction of the RF+DC port electrode and the RF port electrode; the interval between the first inductor L1 and the first resistor R1 is 0.2 to 1mm. With such a setting, the mutual coupling effect is small. The connection direction of the two electrodes in the second inductor L2 is parallel to the connection direction of the RF+DC port electrode and the RF port electrode; the connection direction of the two ends of the second resistor R2 is also parallel to the connection direction of the RF+DC port electrode and the RF port electrode; the interval between the second inductor L2 and the second resistor R2 is 0.2 to 1mm. The end of the second capacitor C2 connected to the ground electrode is not more than 1mm away from its grounding hole 4.
[0038] The following examples illustrate the effect. A broadband bias circuit, the inductance value of the first inductor L1 is 20nH, the inductance value of the second inductor L2 is 200nH, and both use 1.0mm×0.5mm×0.5mm winding inductors to ensure current carrying capacity. The value of the first capacitor C1 is 220pF, the value of the second capacitor C2 is 1000pF, the values of the first resistor R1 and the second resistor R2 are both 500Ω, and the component 1 with a 0.6mm×0.3mm×0.3mm package is selected.
[0039] The overall size of the bias device is 3.0mm×3.0mm×1.3mm. The thickness of the substrate 3 is 0.5mm, the height of the shielding cover 2 is 0.7mm, and the wall thickness is 0.15mm. The bottom of the substrate 3 is divided into four electrodes, namely the RF port electrode, the RF+DC port electrode, the DC port electrode and the ground electrode. The size of the RF port electrode and the RF+DC port electrode is 0.5mm×0.3mm, and the gap between the RF port electrode and the ground electrode is 0.2mm; the size of the DC port electrode is 0.6mm×0.6mm, and the gap between the DC port electrode and the ground electrode is 0.3mm; the area outside the RF port electrode, the RF+DC port electrode, and the DC port electrode is the ground electrode.
[0040] like Figures 8 to 10 As shown, the insertion loss of the final bias tee in the frequency range of 100MHz to 10GHz is less than 1dB, the standing waves of the RF port and RF+DC port are less than 2.0dB, and the isolation between the RF port and the DC port is greater than 30dB, which meets the usage requirements.
[0041] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.
Claims
1. A broadband bias circuit, characterized in that: It includes a first inductor, a second inductor, a first resistor, a second resistor, a first capacitor and a second capacitor; One end of the first inductor and the first capacitor are both connected to the external RF+DC port electrode, the other end of the first capacitor is connected to the external RF port electrode, the other end of the first inductor is connected to the second inductor, and the other end of the second inductor is connected to the external DC port electrode; one end of the second capacitor is connected to the DC port, and the other end of the second capacitor is connected to the external ground electrode; both ends of the first resistor are connected in parallel with the first inductor, and both ends of the second resistor are connected in parallel with the second inductor.
2. A miniaturized broadband bias tee, characterized in that: The invention comprises a broadband bias device circuit, a substrate and a shielding cover as claimed in claim 1; The bottom surface of the substrate is a bias electrode, which is divided into an RF+DC port electrode, an RF port electrode, a DC port electrode and a ground electrode; the top surface of the substrate fixes the broadband bias circuit; the shielding cover is fixed to the top surface of the substrate to encapsulate the broadband bias circuit.
3. The miniaturized broadband bias tweezer according to claim 2, wherein: The connecting line of the RF+DC port electrode and the RF port electrode is parallel to the substrate frame, the RF+DC port electrode is spaced a set distance from the ground electrode, the RF port electrode is spaced a set distance from the ground electrode, and the DC port electrode is spaced a set distance from the ground electrode.
4. The miniaturized broadband bias tweezer according to claim 3, characterized in that: The sizes of the RF+DC port electrode and the RF port electrode are both 0.5mm×0.3mm, and the intervals between the RF+DC port electrode and the RF port electrode and the ground electrode are 0.2mm; the size of the DC port electrode is 0.6mm×0.6mm, and the interval between the DC port electrode and the ground electrode is 0.3mm.
5. The miniaturized broadband bias tee according to claim 3, characterized in that: The connection direction of the two electrodes in the first capacitor is parallel to the connection direction of the RF+DC port electrode and the RF port electrode; the connection direction of the two electrodes in the first inductor is perpendicular to the connection direction of the RF+DC port electrode and the RF port electrode; the connection direction of the two ends of the first resistor is perpendicular to the connection direction of the RF+DC port electrode and the RF port electrode; the end of the second capacitor connected to the ground electrode is no more than 1mm away from the grounding hole.
6. The miniaturized broadband bias tee according to any one of claims 2 to 5, characterized in that: The connection direction of the two electrodes in the second inductor is parallel to the connection direction of the RF+DC port electrode and the RF port electrode; the interval range between the second inductor and the second resistor is 0.2 to 1 mm, and the interval range between the first inductor and the first resistor is 0.2 to 1 mm.