Multi-wire lap wound core inductor
Patent Information
- Application Number
- CN202522449673.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-19
- Publication Date
- 2026-10-27
- Estimated Expiration
- 2035-11-19
AI Technical Summary
这种结构导致匝间与层间存在巨大的分布电容，根据公式 SRF=1/（2π√(L*C))，极大的寄生电容C严重限制了SRF的提升，如图1所示的单根线三层叠绕方式，自谐振频率只能达到175Hz
[0009]本实用新型的有益效果：与现有技术相比，本实用新型效果如下：
Smart Images
Figure CN224907735U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of chip inductor technology, and specifically relates to a multi-wire stacked chip inductor. Background Technology
[0002] In high-frequency applications such as radio frequency circuits, the self-resonant frequency (SRF) of a chip inductor is a key parameter determining its upper operating frequency limit. Traditional wire-wound inductors typically use a single wire with dozens or even hundreds of dense turns to achieve the required inductance. This structure results in huge distributed capacitances between turns and layers. According to the formula SRF = 1 / (2π√(L*C)), the extremely large parasitic capacitance C severely limits the improvement of SRF. Figure 1 The single-wire three-layer winding method shown can only achieve a self-resonant frequency of 175Hz.
[0003] Existing technologies often mitigate this problem by reducing the number of turns or using special wires, but the effects are limited and often sacrifice inductance or cost. Therefore, there is an urgent need for a new type of chip inductor solution that can fundamentally reduce distributed capacitance from a structural perspective. Utility Model Content
[0004] The technical problem to be solved by this utility model is to provide a multi-wire stacked chip inductor that significantly reduces distributed capacitance, thereby increasing the inductor's self-resonant frequency.
[0005] To address the aforementioned technical problems, the present invention adopts the following technical solution: a multi-wire stacked chip inductor, comprising a magnetic core, a winding body, and a UV adhesive layer. The winding body comprises N wires, which are coaxially stacked on the magnetic core in the same direction to form a magnetic core winding structure. Each wire forms a winding layer, where N is an integer greater than or equal to 2. A first end electrode and a second end electrode are provided on the same side of the heads at both ends of the magnetic core. The two leads of the N wires are respectively connected to the first end electrode and the second end electrode on the corresponding side. A UV adhesive layer is wrapped around the bottom of the magnetic core winding structure, and the first end electrode and the second end electrode are located at the top.
[0006] Furthermore, the number of turns made on the aforementioned N wires is equal.
[0007] Furthermore, an insulating isolation layer is provided between the two adjacent winding layers.
[0008] A method for manufacturing a multi-wire lap-wound chip inductor includes the following steps: 1) Core fabrication: A standard 1608 sized magnetic core is made using nickel-zinc ferrite material; 2) Winding the first layer: Use an insulated enameled copper wire as the first conductor, wind 1 turn on the magnetic core to form the first layer of winding, and lead its two ends to one end of the magnetic core; 3) Coating an insulating layer: A layer of dielectric insulating varnish with a thickness of micrometers is coated on the first winding layer and cured to form an interlayer insulating layer; 4) Winding the second winding layer: Repeat steps 2)-3) at least once, and wind the next winding layer on the insulating layer in step 3) and apply the insulating layer until the wire is wound N times and the insulating layer is applied to obtain a multi-wire stacked chip inductor; 5) Forming end electrodes: The first and second end electrodes of the metallized terminals are formed at both ends of the magnetic core by thin film processes (such as sputtering, photolithography, electroplating); 7) Connection: Using laser welding or conductive adhesive bonding, the ends of N wires are connected to the first and second electrodes on the corresponding sides to form a magnetic core coil. 8) Packaging and testing: Apply adhesive to the back of the magnetic core coil on the opposite side of the first and second end electrodes to form a UV adhesive layer, thus completing the manufacturing process.
[0009] The beneficial effects of this utility model are as follows: Compared with the prior art, the effects of this utility model are as follows: (1) Improved Self-Resonant Frequency (SRF): Compared to the traditional long-path, multi-turn single coil, the multi-wire, multi-layer winding method decomposes it into N spatially stacked but electrically independent short-path coils. The physical spacing between these independent coils is much larger than the turn spacing of traditional windings, and there is no cumulative capacitance effect caused by continuous winding of long wires. Therefore, the internal distributed capacitance of the entire inductor is reduced to an extremely low level, thereby achieving a significant improvement in SRF, such as... Figure 4 As shown, the self-resonant frequency of the 3-wire 3-layer lap (blue line) in this application is 194Hz, and the self-resonant frequency of the single-wire multi-layer lap (red line) is 175Hz, which is higher than that of the single-wire multi-layer lap. (2) High frequency characteristics: Since each wire occupies a winding layer independently and is connected to the end electrode, the inherent dense electric field coupling path inside the traditional winding is avoided in terms of structure, making the inductor of this application suitable for high frequency and ultra-high frequency working environments. Attached Figure Description
[0010] Figure 1 This is a schematic diagram of a single-layer structure of a single-wire multi-layer lap-wound chip inductor model; Figure 2 This is a side view of a multi-wire, multi-layer, stacked chip inductor. Figure 3 This is a partially enlarged schematic diagram of the electrode terminal structure; Figure 4 This is a graph showing the comparison of self-resonant frequencies. Detailed Implementation
[0011] The present invention will be further described below with reference to specific embodiments.
[0012] Example 1, such as Figure 2-4 As shown, a multi-wire cascaded chip inductor includes a magnetic core 1, a winding body 2, and a UV adhesive layer 3. The winding body 1 includes N wires, which are coaxially wound on the magnetic core in the same direction to form a magnetic core winding structure. Each wire forms a winding layer, and N is an integer greater than or equal to 2. A first end electrode 4 and a second end electrode 5 are disposed on the same side of the heads at both ends of the magnetic core 1. The two leads of the N wires are respectively connected to the corresponding first end electrode 4 and second end electrode 5. A UV adhesive layer 3 is wrapped around the bottom of the magnetic core winding structure, and the first end electrode 4 and second end electrode 5 are located on top. Each terminal of the first end electrode 4 and second end electrode 5 is insulated from each other. The N wires have an equal number of turns. An insulating layer 6 is disposed between adjacent winding layers.
[0013] Multi-wire lap-wound chip inductors have the following advantages: (1) Improved Self-Resonant Frequency (SRF): Compared to the traditional long-path, multi-turn single coil, the multi-wire, multi-layer winding method decomposes it into N spatially stacked but electrically independent short-path coils. The physical spacing between these independent coils is much larger than the turn spacing of traditional windings, and there is no cumulative capacitance effect caused by continuous winding of long wires. Therefore, the internal distributed capacitance of the entire inductor is reduced to an extremely low level, thereby achieving a significant improvement in SRF, such as... Figure 4 As shown, the self-resonant frequency of the 3-wire 3-layer lap (blue line) in this application is 194Hz, and the self-resonant frequency of the single-wire multi-layer lap (red line) is 175Hz, which is higher than that of the single-wire multi-layer lap. (2) High frequency characteristics: Since each wire occupies a winding layer independently and is connected to the end electrode, the inherent dense electric field coupling path inside the traditional winding is avoided in terms of structure, making the inductor of this application suitable for high frequency and ultra-high frequency working environments.
[0014] Example 2: A method for manufacturing a multi-wire lap-wound chip inductor includes the following steps: 1) Core fabrication: A standard 1608 size magnetic core is made using nickel-zinc ferrite material with excellent high-frequency characteristics; 2) Winding the first layer: Use an insulated enameled copper wire as the first conductor, wind 1 turn on the magnetic core to form the first layer of winding, and lead its two ends to one end of the magnetic core; 3) Coating an insulating layer: A layer of dielectric insulating varnish with a thickness of micrometers is coated on the first winding layer and cured to form an interlayer insulating layer; 4) Winding the second winding layer: Repeat steps 2)-3) at least once, and wind the next winding layer on the insulating layer in step 3) and apply the insulating layer until the wire is wound N times and the insulating layer is applied to obtain a multi-wire stacked chip inductor; 5) Forming terminal electrodes: Metallized terminals, specifically the first and second terminal electrodes, are formed at both ends of the magnetic core using thin-film processes (such as sputtering, photolithography, and electroplating). Figure 2-3 As shown; 7) Connection: Using laser welding or conductive adhesive bonding, the ends of N wires are connected to the first and second electrodes on the corresponding sides to form a magnetic core coil. 8) Packaging and testing: Apply adhesive to the back of the magnetic core coil on the opposite side of the first and second end electrodes to form a UV adhesive layer, thus completing the manufacturing process.
[0015] like Figure 4 As shown, the self-resonant frequency of the 3-wire 3-layer lap (blue line) in this application is 194Hz, while the self-resonant frequency of the single-wire multi-layer lap (red line) is 175Hz, which is higher than that of the single-wire multi-layer lap.
Claims
1. A multi-wire lap-wound chip inductor, characterized in that, The magnetic core includes a winding body and a UV adhesive layer. The winding body includes N wires, which are coaxially wound on the magnetic core in the same direction to form a magnetic core winding structure. Each wire forms a winding layer. N is an integer greater than or equal to 2. A first end electrode and a second end electrode are provided on the same side of the heads at both ends of the magnetic core. The two leads of the N wires are respectively connected to the first end electrode and the second end electrode on the corresponding side. The bottom of the magnetic core winding structure is wrapped with a UV adhesive layer, and the first end electrode and the second end electrode are located on the top.
2. The multi-wire lap-wound chip inductor according to claim 1, characterized in that, The number of turns of N wires are equal.
3. The multi-wire lap-wound chip inductor according to claim 1, characterized in that, An insulating layer is provided between two adjacent winding layers.