Position:Home » Industry News
Microhm Electronics' Sense Resistor for Motor Control
Writer:Microhm Page View:Date:2020-01-03
The use of current sense resistors, such as Microhm Electronics shunt resistors, is part of a trend in motor control system design that benefits from adopting new digital isolation technologies. These technologies offer higher reliability levels to designers based on the introduction of the component level standard IEC 60747-17, which specifies the performance, test, and certification requirements for capacitive and magnetically coupled isolators.
Digital control of a motor drive incorporates current sense resistors for sensing winding current. The article offers recommendations for selecting the best current sense resistor for this application.
Given that the output of the AD7403 is a 16-bit number, the potential accuracy of the current measurement is limited not by the ADC conversion, but by the voltage reading itself. The drift of the resistance with temperature will vary depending on the material used in the resistor element, as well as the power rating and the actual physical size of the component.
Resistive elements made up of special alloys of nickel, copper, and manganese have parabolic resistance drift curves, these alloys are the most accurate materials used for current sensing applications. Microhm MMS4026 is such kind a shunt resistor.
Let us use Microhm Electronics' part number MMS4026L500F for calculating the resistance drift at full power and at an ambient temperature of 70°C. MMS4026L500F is a 0.5 mΩ (±1%) sense resistor rated to 5 watts of power, at a maximum ambient temperature of 130°C. It derates from 100% power to 0 W at 170°C. The thermal resistance of the component therefore, is 8°C/W. At full power and an ambient temperature of 70°C, we can expect the surface temperature of the component to reach 110°C.
Digital control of a motor drive incorporates current sense resistors for sensing winding current. The article offers recommendations for selecting the best current sense resistor for this application.
Given that the output of the AD7403 is a 16-bit number, the potential accuracy of the current measurement is limited not by the ADC conversion, but by the voltage reading itself. The drift of the resistance with temperature will vary depending on the material used in the resistor element, as well as the power rating and the actual physical size of the component.
Resistive elements made up of special alloys of nickel, copper, and manganese have parabolic resistance drift curves, these alloys are the most accurate materials used for current sensing applications. Microhm MMS4026 is such kind a shunt resistor.
Let us use Microhm Electronics' part number MMS4026L500F for calculating the resistance drift at full power and at an ambient temperature of 70°C. MMS4026L500F is a 0.5 mΩ (±1%) sense resistor rated to 5 watts of power, at a maximum ambient temperature of 130°C. It derates from 100% power to 0 W at 170°C. The thermal resistance of the component therefore, is 8°C/W. At full power and an ambient temperature of 70°C, we can expect the surface temperature of the component to reach 110°C.
Keywords:Sense Resist
Latest News
- Resistor's role in measuring and correcting LED,,,
- Single through-hole resistors' characteristics ,,,
- Why shunt resistors for current sense applicati,,,
- Metal-film resistors with small size, high resi,,,
- 36W High-Current Shunt Resistors MMS8420,,,
- 1W Surface Mount Resistor MPR1206,,,
- An Overview of Microhm Electronics' Resistor Pr,,,
- More anti-sulfur resistors used in harsh envir,,,
- Resistance changes with temperature,,,
- 140W TO247 High Power Heatsinkable Resistor,,,
- MMS5930 is ideal for current sensing in industr,,,
- Shunt resistors selection for engineers' design,,,
- Considerations for choosing precision resistors,,,
- Ceramic Encased Cement Resistors NWH Series for,,,
- Resistors for Passive Balancing in Battery-Pow,,,
Hot Articles
- Microhm will take part in 10th Automotive World,,,
- Thanks for Visiting Microhm's Booth E5-5706 in ,,,
- Resistors in Short Supply: Blame Cars,,,
- New lunch: High Power Precision Shunt Resistor,,,,
- How to Test a Resistor,,,
- Innovative Technology, Future Electric: Electri,,,
- What is Precision Resistors?,,,
- SMD Resistors Sizes and Packages,,,
- The Construction and Features of Metal Film Res,,,
- What is a TO-220 Resisor?,,,
- Hot Selling Products: Precision Shunt Resistors,,,
- How to Calculate the Equivalent Resistance Valu,,,
- What is a Fixed Resistor?,,,
- Resistors in LED Circuits,,,
- Resistors Types and Materials Overview,,,
Resistance applications
- Precision Resistors' Construction and TCR,,,
- The Main Application for High Precision and Low,,,
- Difference Between High Precision Resistors and,,,
- Surface Mount Resistor's Size and Package ,,,
- The Four Important Functions of Alloy Resistors,,,
- Why Zero-Ohm Resistors?,,,
- The Measurement Accuracy of Automotive Shunt is,,,
- Carbon Film Resistors' Features and Application,,,
- Select the Right Resistor for Harmonic Filterin,,,
- Shunt Resistor MMS8420 for High Current Stable ,,,
- Miniature future for passive electronic compone,,,
- BMS for New Energy Vehicle,,,
- Industrial Roberts Applied to Solar Photovoltai,,,
- Heater Blower Motor Resistor in Air Conditioner,,,
- Urbanization Development Bringing the Transform,,,