Four-terminal resistor
By designing a centrally symmetrical four-terminal resistor, the problems of current and voltage signal interference and processing and assembly difficulties were solved, thereby improving the accuracy and precision of signal acquisition and simplifying the processing and assembly process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ANHUI YUANXU ELECTRONIC TECH DEV CO LTD
- Filing Date
- 2025-03-19
- Publication Date
- 2026-05-01
AI Technical Summary
Existing resistors suffer from current and voltage signal interference, leading to signal acquisition deviations. They are also difficult to manufacture and assemble, especially the asymmetrical structure of four-terminal resistors, which further complicates manufacturing and assembly.
The design incorporates a centrally symmetrical four-terminal resistor with centrally symmetrical voltage sampling points and terminal electrodes. The voltage sampling points are isolated from the current inlet points, and the contact area between the electrodes and the circuit board is increased. Thermally conductive materials and protective layers are used to isolate the electrodes and voltage sampling points, ensuring a uniform current density distribution.
It reduces interference from current and voltage signals, improves the accuracy of signal acquisition, enhances measurement precision and power consumption, and simplifies the processing and assembly process.
Smart Images
Figure CN224190743U_ABST
Abstract
Description
A four-terminal resistor Technical Field
[0001] This utility model relates to the field of resistor technology. Background Technology
[0002] With the advancement of electronic product performance and the increasing demands for precision, precision resistors are required to possess higher accuracy, smaller resistance values, and higher power handling capabilities. Currently, resistors primarily utilize a two-terminal structure, with the two terminals serving as conductive electrodes across the resistor body. When voltage is measured from a resistor, a voltage detection device is connected to these conductive electrodes. However, since current also flows through these electrodes in the circuit, interference between the current and voltage signals can cause signal acquisition errors. Conventional resistors often achieve lower resistance values by adding internal electrodes or using complex electrode structures, but these methods can lead to problems such as increased or uncontrollable TCR (Total Resistance Change) and reduced power handling.
[0003] Furthermore, the commonly used four-terminal resistor structure in the prior art is shown in Figure 1. Because this structure is an asymmetrical design, the directional polarity of the product needs to be considered when processing and assembling the resistor. If the processing or assembly of this asymmetrical structure is opposite to the design directional polarity, the product will be unusable. Therefore, this structure increases the difficulty of resistor processing and assembly.
[0004] Therefore, a new technical solution is needed to solve the above-mentioned technical problems. Summary of the Invention
[0005] To address the above problems, the purpose of this invention is to provide a four-terminal resistor that can reduce interference with current and voltage signals and make the voltage acquisition signal more accurate.
[0006] A further objective of this invention is to address the problem of the high difficulty in processing and assembling resistors in the prior art.
[0007] To achieve the above-mentioned objectives, the four-terminal resistor of this utility model can adopt the following technical solution:
[0008] A four-terminal resistor includes a resistance alloy, a substrate carrying the resistance alloy, an adhesive film located between the resistance alloy and the substrate, end face electrodes located at both ends of the bottom of the resistance alloy, and two voltage sampling points located at the bottom of the resistance alloy, with the two voltage sampling points located between the end face electrodes at both ends.
[0009] Furthermore, the two voltage sampling points are designed with the center of the resistance alloy in a centrally symmetrical manner, and the two end-face electrodes are also designed with the center of the resistance alloy in a centrally symmetrical manner.
[0010] Furthermore, the length of the end face electrode is less than the length of the voltage sampling point, and the length of the voltage sampling point is the same as the width of the bottom surface of the resistance alloy.
[0011] Furthermore, the distance between adjacent end face electrodes and voltage sampling points is not less than 0.1 mm.
[0012] Furthermore, the voltage sampling point is made of copper, gold, silver, nickel, or tin; the substrate is made of ceramic, FR4, or polyimide.
[0013] Furthermore, the resistance alloy is at least one of manganese copper, copper manganese tin, nickel chromium aluminum silicon, copper manganese nickel, and iron chromium alloy.
[0014] Furthermore, the lower surface of the resistance alloy is covered by a protective layer; the area under the protective layer is divided into multiple regions by voltage sampling points.
[0015] Beneficial effects: Compared with existing technologies, the significant advantages of this four-terminal resistor are: the voltage acquisition point is isolated from the current input point, avoiding signal acquisition deviation caused by interference between current and voltage signals; the voltage acquisition point is located close to the middle area of the resistor alloy body, and when the resistor is connected to the circuit board, both electrodes and two voltage acquisition points are in contact with the circuit board simultaneously. Compared with the two-terminal resistors in the prior art, the contact area between the metal layer of the resistor and the circuit board in this solution is increased, which is conducive to heat dissipation in this area and improves the power consumption of the product; at the same time, the electrode terminals and voltage acquisition points of this solution present a centrally symmetrical design, and the current density distribution is more uniform, which is conducive to improving the measurement accuracy of the product and avoiding the problem of directional polarity identification during processing and assembly. Attached Figure Description
[0016] Figure 1 is a schematic diagram of the structure of a four-terminal resistor in the prior art;
[0017] Figure 2 is a bottom view of the product structure according to an embodiment of the present utility model;
[0018] Figure 3 is a side view of the product structure according to an embodiment of the present invention. Detailed Implementation
[0019] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0020] Referring to Figures 2 and 3, this utility model provides a four-terminal resistor, which includes end-face electrodes 1, voltage sampling points 2, a protective layer 3, a substrate 4, a resistance alloy 5, and an adhesive film 6. The two end-face electrodes 1 are located at the bottom ends of the resistance alloy, and the two voltage sampling points 2 are also located at the bottom of the resistance alloy, situated between the end-face electrodes 1 at both ends. The two voltage sampling points 2 are centrally symmetrical about the center of the end-face electrodes 1, and the two end-face electrodes 1 are also centrally symmetrical about their center. Therefore, no special consideration of directional polarity is required during processing, and the resistor can still be assembled and used even if rotated 180°, avoiding orientation identification problems during processing and assembly.
[0021] The end electrode 1 and voltage acquisition point 2 are made of low-resistivity, high-thermal-conductivity metal materials such as copper, nickel, tin, silver, and gold, or their alloys. The resistance alloy 5 is made of one of the following: manganese-copper alloy, nickel-chromium alloy, iron-chromium alloy, or titanium-tungsten alloy. The cross-sectional area of the resistance alloy 5 is reduced by cutting patterns or thinning the surface using laser repair, mechanical methods, etc., to achieve the preset resistance value. The adhesive film 6 is made of a thermally conductive material with a thickness of 12.5-50 μm and a thermal conductivity of 3-5 W / mK. The bonding temperature is 160-180℃, and the pressure is 3-5 kg / cm². 2. .
[0022] The surface of the resistance alloy 5 is covered with a protective layer 3; the space between the electrode 1 and the voltage sampling point 2 is filled with a protective layer 3 to achieve isolation between them.
[0023] Electrode 1 and voltage sampling point 2 are composed of a copper layer, a nickel layer and a tin layer. The copper layer is more than 50 μm thick, and the nickel and tin layers are more than 5 μm thick. The copper layer increases thermal conductivity, the nickel layer serves as a connecting layer to increase the bonding force between the copper and tin layers, and the tin layer increases the solderability of the current detection resistor.
[0024] When the current sensing resistor is working, the resistance alloy 5 makes contact with the circuit board through the electrode 1 and the voltage sampling point 2, which enables the heat generated by the resistance alloy to be quickly transferred into the circuit board, thereby reducing the temperature of the resistance alloy 5 and improving the power and performance of the current sensing resistor.
[0025] When the current sensing resistor is working, the current path and voltage path are physically isolated, reducing interference between current input and voltage acquisition, which is beneficial for precise measurement.
Claims
1. A four-terminal resistor, characterized in that, It includes a resistance alloy (5), a substrate (4) that carries the resistance alloy (5), a film (6) located between the resistance alloy (5) and the substrate (4), end face electrodes (1) located at both ends of the bottom of the resistance alloy (5), and two voltage sampling points (2) located at the bottom of the resistance alloy (5), with the two voltage sampling points (2) located between the end face electrodes (1) at both ends.
2. The four-terminal resistor of claim 1, wherein, The two voltage sampling points (2) are designed to be centrally symmetrical with respect to the center of the resistance alloy (5), and the two end face electrodes (1) are also designed to be centrally symmetrical with respect to the center of the resistance alloy (5).
3. The four-terminal resistor of claim 1 or 2, wherein The length of the end face electrode (1) is less than the length of the voltage sampling point (2), and the length of the voltage sampling point (2) is the same as the width of the bottom surface of the resistance alloy (5).
4. The four-terminal resistor as described in claim 1 or 2, characterized in that, The distance between adjacent end face electrodes (1) and voltage sampling points (2) is not less than 0.1 mm.
5. The four-terminal resistor of claim 1, wherein, The voltage sampling point (2) is made of copper, gold, silver, nickel or tin; the substrate (4) is made of ceramic, FR4 or polyimide.
6. The four-terminal resistor of claim 1, wherein, The resistance alloy (5) is at least one of manganese copper, copper manganese tin, nickel chromium aluminum silicon, copper manganese nickel, and iron chromium alloy.
7. The four-terminal resistor as described in claim 1, characterized in that, The lower surface of the resistance alloy (5) is covered by a protective layer (3); the protective layer (3) is divided into multiple regions by voltage sampling points (2).