8results about How to "High resistance precision" patented technology

The invention belongs to the technical field of printed circuit boards, and relates to a buried resistor copper foil and a preparation method and application thereof. In the preparation of the buried resistance copper foil, the film with the window is selected to be attached to the upper surface and the lower surface of the copper foil, the copper foil with the resistance window is obtained through etching, then the resistance layer is directly and electrically deposited in the resistance window of the copper foil, and then the film is removed to obtain the buried resistance copper foil. The method can effectively reduce the resistance value difference of the unit area of each square resistance layer on the copper foil so as to improve the resistance value precision of the embedded resistance copper foil, and the preparation process is simple and easy to operate.

The invention discloses an intelligent rehabilitation training instrument for brain and limb diseases. The intelligent rehabilitation training instrument comprises a base and a testing mechanism. The testing mechanism comprises a supporting table movably installed on the base, a seat is connected to the supporting table in a sliding mode, the seat can be driven to move and generate pressure on first pressure sensors, and the pressure applied to the feet of the patient can be detected through two second pressure sensors; the ankle rehabilitation training mechanism is used in cooperation with the testing mechanism; the testing mechanism can control the resistance of the pedal driven by the movement of the feet of the patient according to values measured by the first pressure sensor and the second pressure sensor. According to the device, the force exerting degree of the feet of the patient is detected through the testing mechanism, the flowing area of fluid through the fluid holes can be controlled, then the resistance generated when the pedal is driven to rotate is controlled, rehabilitation training can be accurately conducted on the ankles of the patient, the rehabilitation training effect is improved, and some unnecessary rehabilitation training is avoided.

The present invention discloses a chip heater and its manufacturing process, including a carrier layer, a heating layer and a copper foil welding layer, the carrier layer has a plurality of carrier substrates arranged in sequence, each carrier substrate is composed of a high temperature resistant glass fiber cloth and a colloid layer positioned on the front of the high temperature resistant glass fiber cloth; the heating layer is positioned on the front of the carrier layer, the copper foil welding layer is positioned on the back of the carrier layer, and the heating layer is also connected with the copper foil welding layer; a heating layer pattern is etched on the front of the heating layer, a welding layer pattern is etched on the back of the copper foil welding layer, and a photosensitive epoxy resin packaging layer is respectively encapsulated in the middle of the heating layer pattern and the middle of the welding layer pattern, and a tin-plated layer is electroplated on the remaining parts of the heating layer pattern and the welding layer pattern. The chip heater prepared by the present invention is not only novel and reasonable in structure, but also has low power consumption, high resistance value accuracy, high power stability, is not easily damaged by external forces, and has a long product service life.

The present application discloses a resistance measurement circuit, a resistance measurement method and a digital multimeter. The resistance measurement circuit includes a constant voltage power supply circuit, a resistor array circuit, a current protection circuit and an analog-to-digital conversion circuit. The current protection circuit is used for overcurrent protection, the constant voltage power supply circuit is used to provide a constant voltage power supply, the resistor array circuit is used to select and connect a reference resistor with a known resistance value, and the analog-to-digital conversion circuit is used to obtain the voltage value at both ends of the resistor to be measured and the voltage value at both ends of the reference resistor with a known resistance value, and obtain the resistance value of the resistor to be measured according to the voltage value at both ends of the resistor to be measured, the resistance value of the reference resistor and the voltage value at both ends of the reference resistor. By using the voltage at both ends of the reference resistor as the reference voltage of the analog-to-digital converter, the measurement accuracy of the resistor to be measured is only related to the number of bits of the analog-to-digital converter and the resistance value accuracy of the reference resistor. Since the factors affecting the measurement accuracy are reduced, the measurement accuracy of the resistance value is greatly improved.

This solution provides a design method and electronic device for composite resistive pastes with target resistance values. It uses the resistance parameter sets and mixing ratios of each composite resistive paste and corresponding first and second resistive pastes as training data sets. The training data sets and parameter acquisition instructions are input into a regression prediction model for training, outputting optimized resistance parameters and the optimal number of regression equation terms. The target resistance value of the composite resistive paste and the optimized resistance parameters of the first and second resistive pastes are used as prediction parameter sets. The prediction parameter sets and prediction instructions are input into the trained regression prediction model, outputting the predicted mixing ratio of the first and second resistive pastes, thereby achieving efficient design of composite resistive pastes with target resistance values.

The invention discloses a manufacturing method suitable for an alloy foil resistor. The manufacturing method comprises the following steps: 1, curing a substrate and pasting a film; 2, pattern transfer; 3, developing, etching and removing the film; 4, printing a protective layer before rack plating; 5, exposing and developing the protective layer before rack plating; 6, rack plating; 7, plating bridge cutting; 8, precisely adjusting the resistance; 9, printing a protective layer; 10, marking and printing; 11, the protection layer mark is cured; 12, laser scribing; 13, performing primary segmentation; 14, performing vacuum sputtering; 15, carrying out secondary segmentation; sixthly, barrel plating of copper, nickel and tin is conducted. According to the invention, by introducing an innovative alloy foil resistor manufacturing process, the resistance precision of the alloy foil resistor is greatly improved, the purpose of automatic resistance adjustment of the high-precision alloy foil resistor is achieved, and the stability and consistency of the product are improved.

The application provides a platinum thin film and a manufacturing method thereof, and the manufacturing method comprises the following steps: performing chemical mechanical polishing treatment on a ceramic substrate by using a polishing liquid to obtain a ceramic substrate with a predetermined roughness; depositing a platinum thin film on the ceramic substrate by using a magnetron sputtering method at a predetermined substrate temperature; and performing annealing treatment on the platinum thin film. The platinum thin film prepared by using the chemical mechanical polishing treatment and the multiple sputtering method has the advantages of thin thickness, low square resistance, high uniformity and low cost, and the electrical performance of the platinum thin film with thin thickness is equivalent to that of a thick film, the production cost is reduced while the good performance is ensured. Therefore, when the platinum thin film is applied to a resistance temperature sensor, the resistance temperature sensor can not only meet the requirement of accurate measurement of the environmental temperature of the resistance temperature sensor product, but also reduce the production cost of the resistance temperature sensor and improve the production efficiency.

This utility model relates to the field of stainless steel resistance regulators and discloses a resistance regulator, comprising a resistance regulator with two outer shells on both sides, which are connected by a second outer shell. A base plate is installed at the bottom of the resistance regulator, and a heat dissipation vent is provided on the outer side of the second outer shell. A high-power stainless steel resistance regulator is used to replace the wire diameter resistor, and the resistance value can be adjusted to replace the change in wire diameter and length. The regulator has a certain resistance value sliding adjustment function. Utilizing Ohm's law, U=IR, voltage is the product of current and resistance. When the resistance R is fixed, the larger the current flowing through the resistor, the larger the voltage drop. Therefore, various voltages can be generated across the resistor by changing the resistance, which meets the output voltage and current index verification of various constant current source power supplies. The stainless steel resistance regulator has high resistance accuracy during field testing, and its operation is simple and the process is simplified.