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If you are tired of scale buildup, scratchy laundry, or cloudy glassware, it’s probably time to take hard water into your own hands, literally. This blog delves into inventive, affordable, and unexpectedly easy design concepts for building your own electronic water softener.

Whether you are an engineer armed with blueprints or a hands-on do-it-yourself enthusiast ready to roll up your sleeves, the pointers shared here will help you transform a persistent plumbing issue into a smooth-flowing success.

So, what’s an electronic water softener (descaler)? It’s a simple oscillator circuit tailored to create a magnetic field around a water pipe to reduce the chances of smaller deposits sticking to the inside of the pipes.

Not new, the concept of water conditioning dates back to the 1930s. Hard water has a high concentration of minerals, the most abundant of which is calcium particles. The makeup of deposits leads to the term hard water and reduces the effectiveness of soaps and detergents. Over time, these tiny deposits can stick to the inside of pipes, clog filters, faucets and shower heads, and leave residue on kettles.

The idea behind the electronic/electromagnetic water softener is that a magnetic field around the water pipe causes calcium particles to clump together. Such a system consists of two coils wound around the water pipe with a gap between them.

The circuit driving them is often a high frequency oscillator that generates pulses of 15 kHz or so. As a result, large particles are formed, which pass through the water pipe and do not cling to the inside.

Thus, the electronic water softener operates by wrapping coils of wire around the incoming water main to pass a magnetic field through the water. This causes the calcium in the water to stay in solution, thereby bottling it up from clinging to taps and kettles. Also, the impact of electromagnetic flux makes the water physically soft as the magnetic flux breaks the hard molecules and makes it soft by nature.

Below is a visual summary of the process.

Figure 1 The original image was sourced from Google Images and has been retouched by author for visual clarity.

Most electronic descalers typically operate with two coils to increases the time for which the water is exposed to the electromagnetic waveform, but a few use only one coil.

Figure 2 Here is how electronic descalers operate with two coils or one coil. Source: Author

A quick inspection of the most common water softener circuits found on the web shows that the drive frequency is about 2 to 20 kHz in the 5- to 15-V amplitude range. The coils to be wound outside the pipe are just about 20- to 30-turn inductors made of 18 to 24 SWG insulated or copper wire.

It has also been noted that neither the material of the water pipe (PVC or metal) nor its diameter has a significant effect on the efficiency of the lime solver.

When I stumbled upon a blogpost from 2013, it felt like the perfect moment to explore the idea more deeply. This marks the beginning of a hands-on learning journey—less of a formal project and more of a series of small, practical experiments and functional blueprints.

The focus is not on making a polished product, but on picking up new skills and exploring where the process leads. So, after learning from several sources about how electronic water softeners work, I decided to give it a try.

The first step in my process involved developing a universal (and exploratory) driver circuit for the pipe coil(s). The outcome is shown below.

Figure 3 The schematic shows a driver circuit for the pipe coil. Source: Author

Below is the list of parts.

• C1 and C2: 470 uF/25 V
• C3: 1,000 uF/25 V
• D1: 1N4007
• L1: 470 uH/1 A
• IC1: MC34151

Note that the single-layer coil L2 on the 20-mm diameter PVC water pipe is made of around 60 turns of 18AWG insulated wire. The single-layer coil on pipe has an inductance of about 20 uH when measured with an LCR meter. The 470 uH drum core inductor L1 (empirically selected part) throttles the peak current through the pipe coil L2.

A single-channel MOSFET gate driver is adequate for IC1 in this setup; however, I opted for the MC34151 gate driver during prototyping as it was readily on hand. Next comes a bit different blueprint for the pipe coil driver.

Figure 4 Arduino Uno was used to drive the pulse input of the pipe coil driver circuitry. Source: Author

To drive the pulse input of the pipe coil driver circuitry, an Arduino Uno was used (just for convenience) to generate a sweeping frequency between 500 Hz and 5 kHz (the adapted code is available upon request). Although selected without a specific technical justification, this empirically optimized range has demonstrated enhanced performance in some targeted zones.

At this stage, opting for a microcontroller-based oscillator or pulse generator is advisable to ensure scalability and facilitate future enhancements. That said, a solution using discrete components continues to be a valid choice (an adaptable textbook pointer is provided below).

Figure 5 An adaptable textbook pointer highlights the above solution. Source: Author

Nevertheless, the setup ought to be capable of delivering a pulsed current that generates time-varying magnetic fields within the water pipe, thereby inducing an internal electric field. For optimal induction efficiency, a square-wave pulsed current is always advocated.

The experiment is still ongoing, and I am drawing a tentative conclusion at this stage. But for now, it’s your chance to dive in, experiment, and truly make it your own.

T. K. Hareendran is a self-taught electronics enthusiast with a strong passion for innovative circuit design and hands-on technology. He develops both experimental and practical electronic projects, documenting and sharing his work to support fellow tinkerers and learners. Beyond the workbench, he dedicates time to technical writing and hardware evaluations to contribute meaningfully to the maker community.

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• DIY Water Softener System
• Power Indicator for the Water Softener

The post Electronic water softener design ideas to transform hard water appeared first on EDN.

Automotive Grade Device Delivers Luminous Intensity to 2800 mcd, Enables Every Color Within the Gamut Triangle Inside the CIE 1931 Color Space

Vishay Intertechnology, Inc. introduced a new tricolor LED that provides luminous intensity to 2800 mcd at 20 mA for interior automotive lighting, RGB displays, and backlighting. Featuring separate anode and cathode connections for the red, green, and blue LED chips inside its compact 3.5 mm by 2.8 mm by 1.4 mm PLCC-6 surface-mount package, the Automotive Grade VLMRGB6122..enables individual control of each chip, making it possible to realize every color within the color room defined by the gamut triangle area inside the CIE 1931 color space through color mixing.

With its wide color range, the Vishay Semiconductors LED released, is ideal for ambient lighting, switch illumination, status indicators, and dashboard signal and symbol illumination in automobiles; large-format, full-color message and video display boards; backlighting in consumer devices, home appliances, medical instrumentation, and telecom equipment; and a wide range of accent and decorative lighting. For these applications, the device utilizes the latest high brightness AllnGaP and InGaN technologies to deliver 70 % higher brightness than previous-generation solutions in a package with a 22 % lower profile than competing products.

Providing high reliability, the VLMRGB6122..offers a wide temperature range from -40 °C to +110 °C, which is 25 °C higher than standard solutions, and Class B1 corrosion robustness. The LED is AEC-Q102 qualified, offers a Moisture Sensitivity Level (MSL) of 3, and withstands ESD voltages up to 2 kV for red and 8 kV for blue and green in accordance with JESD22-A114-B. RoHS-compliant, halogen-free, and Vishay Green, the device is compatible with IR reflow soldering and categorized per reel for luminous intensity, color, and forward voltage.

The post Vishay Intertechnology RGB LED in PLCC-6 Package Provides Independent Control of Red, Green, and Blue Chips for Wide Color Range appeared first on ELE Times.

In an exclusive interview with ELE Times, Mr. Brahmanand Patil, President & Managing Director of Vector Informatik India Pvt. Ltd., shed light on how Vector is driving the transformation of aerospace networks. The conversation ranged from TSN adoption to state-of-the-land cybersecurity, FACE compliance, and digital twins, with Vector sharing some insights about the technologies driving the current aerospace platforms. Excerpts.

ELE Times: What Vector is seeing in aerospace in the latest trends in the implementation of Time Sensitive Networking (TSN)?

Brahmanand Patil: We are seeing a growing adoption of Ethernet-based TSN for deterministic, synchronized, high-bandwidth avionics data. Aerospace OEMs increasingly prefer TSN over legacy buses (e.g., ARINC 429/FIBRE) to meet scaling demands for data communications among flight control, sensors, and mission systems.

At Vector, we are responding to this shift with TSN support in test tools, enabling aerospace developers to validate deterministic timing, redundant paths, and strict QoS behaviors on Ethernet.

ELE Times: How do Vector tools like CANoe.AFDX and VN interface hardware assist in testing high-reliability aerospace communication systems?

Brahmanand Patil: Reliability is non-negotiable in aerospace—and our tools are designed with that in mind. CANoe.AFDX supports simulation and conformance testing of AFDX (ARINC 664) and Ethernet-based avionics networks. It can inject faults, simulate redundant virtual links, verify timing requirements, and validate configuration against STDs like DO-160.

VN interface hardware like VN1600, VN5610 enables real-time physical-layer interaction, traffic generation, and measurements over Ethernet/AFDX/TSN. This lets engineers capture jitter, latency, packet errors, and link redundancy performance in real aircraft or Hardware-In-Loop (HIL) setups. These tools ensure avionics comms meet stringent reliability and timing metrics.

ELE Times: How does Vector support the development of software for FACE-compliant avionics platforms?

Brahmanand Patil: Vector’s toolchain integrates with model-based development (Simulink, SCADE, etc.) and supports code generation tailored to FACE Technical Standard running on POSIX or specialized FACE OS platforms. CANoe’s test framework can simulate face component interfaces, verify misuse cases, and perform regression testing across FACE segments: Safety-critical, Portable, and I/O.

Vector also enables integration testing in multi-vendor FACE environments, ensuring interoperability and that interfaces meet FACE conformance.

ELE Times: How is Vector integrating cybersecurity features (like secure communication or authentication) into its tools for aerospace applications?

Brahmanand Patil: At Vector, cybersecurity is not an afterthought—it’s embedded into the DNA of our tools for avionics. Our solutions enable rigorous testing and validation of secure communication protocols such as TLS, DTLS, IPsec, and secure extensions of AFDX. Using CANoe, aerospace developers can simulate and verify handshake mechanisms, certificate-based authentication, encryption throughput, and resilience against protocol-level anomalies.

Our network interfaces, including VN adapters, support precise packet-level timestamping and real-time capture of secure traffic—empowering developers to assess encryption overhead and identify tampering or injection attempts.

To further strengthen avionics systems, CANoe integrates powerful cyber-attack simulation capabilities like fuzzing, allowing stress testing against DoS, replay, and malformed packet attacks in Ethernet or AFDX-based networks.

On the software assurance front, VectorCAST delivers high-integrity testing across all development phases—from unit to system-level—aligned with DO-178C and DO-330 guidelines. With its data/control coupling analysis, VectorCAST ensures that inter-component communication adheres strictly to intended interfaces, helping eliminate side-channel risks and unauthorized data paths.

For static code analysis, PC-lint Plus acts as a robust SAST (Static Application Security Testing) tool. It enables early detection of vulnerabilities such as buffer overflows, memory corruption, and unsafe typecasts, aligned with industry standards like CWE, CERT C, MISRA, and AUTOSAR—minimizing attack surfaces in mission-critical avionics code.

By combining simulation, attack emulation, runtime monitoring, and static analysis under one roof, Vector provides aerospace engineers with an integrated platform to design, validate, and secure next-generation embedded systems.

ELE Times: What advancements is Vector making in cybersecure data communication in avionics networks?

Brahmanand Patil: Vector is enhancing its toolset with secure gateway emulation—including cybersecurity policies, firewall rules, and key-management scenarios—aligned with industry standards like DO-326A/ED-202A.

They’re also enabling encrypted redundant TSN path validation, where tools simulate failover in secure real-time Ethernet environments.

Support for capturing PHY-level anomalies, example ARINC 429 vulnerabilities hints at path toward intrusion detection, signal anomaly capture, and side-channel audit—it aligns with academia’s move toward voltage-based IDS

On the software side, Vector integrates Common Weakness Enumeration (CWE) into its PC-lint Plus static analysis tool. This enables early detection of critical vulnerabilities such as buffer overflows, memory mismanagement, and logic flaws—common risks in avionics data communications. Catching such issues early in development is vital for maintaining the integrity of flight-critical systems.

PC-lint Plus further acts as a Static Application Security Testing (SAST) solution aligned with DO-178C objectives. It supports high-integrity development through structural code analysis and enforces compliance before integration phases.

To ensure industry-grade secure coding, PC-lint Plus supports coding standards including:

• CERT C – Secure programming practices.
• MISRA C/C++ – Reliable and safe coding for critical systems.
• AUTOSAR C++14 – Standardized architecture for embedded automotive and avionics platforms.

Together, these capabilities enable aerospace developers to build secure, interoperable, and standards-compliant communication systems that are resilient against modern cybersecurity threats.

ELE Times: How does Vector leverage digital twin technologies in aerospace network validation?

Brahmanand Patil: The capabilities of CANoe and Interface hardware offer high-fidelity virtual replication of avionics networks; this effectively serves as a digital twin.

Through link-level simulation (AVIONICS + TSN), fault injection, deterministic latency modeling, and integration with physical hardware in HIL (hardware-in-the-loop) configurations, Vector supports the same iterative validation, anomaly detection, and real-time monitoring goals touted in digital twin use cases.

The post Powering Intelligent Avionics: How Vector is Advancing TSN, FACE, and Cybersecurity appeared first on ELE Times.

Підписано меморандум про співпрацю у сфері кібербезпеки та цифровізації kpi чт, 07/17/2025 - 02:31

My First Post (So don't mind the presentation 😅) Hi, Aadit Sharma here 👋 I'm 18 and about to begin my journey in Electronics and Communication Engineering. This is my ongoing personal project — a 4-bit transistor-level computer built entirely from scratch, using only discrete components on breadboards. No microcontrollers, no ICs — just hundreds of 2N2222A transistors, resistors, and wires! So far, I've used around 600 transistors (and counting). Completed modules: ALU Registers Memory Opcode Decoder Clock Circuit This project is my way of understanding how computers work from the ground up — one gate, one wire at a time. As far as progress goes, 60% has been built in last 2 months, I have estimated 2 months more for completion. This has 5 instruction set as of now, which are - (Halt, Add, Sub, Out, Clear) 🔧 Inspired from - Global Science Network(YT channel) More updates would be done according to progress Stay tuned! submitted by /u/Aadit21 [link] [comments]

Nanotechnology firm UbiQD Inc of Los Alamos, NM, USA has entered into an exclusive, multi-year agreement to supply its proprietary fluorescent quantum dot (QD) technology to cadmium telluride (CdTe) thin-film photovoltaic (PV) module maker First Solar Inc of Tempe, AZ, USA. The agreement paves the way for the incorporation of QD technology into First Solar’s thin-film bifacial photovoltaic (PV) solar panels...

Why does the task of circuit debugging keep getting complex year by year? It’s no longer looking at the schematic diagram and sorting out the signal flow path from input to output. Here is a sneak peek at the factors leading to a steady increase in challenges in debugging electronics circuits. It shows how the intermingled software/hardware approach has made prototyping electronic designs so complex.

Read the full blog on EDN’s sister publication, Planet Analog.

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The post What makes today’s design debugging so complex appeared first on EDN.

From January 5, 2024, please see: “The dangers of light glare from high-brightness LEDs.”

I have just become aware that at least one state has wisely chosen to address the safety issue of automotive headlight glare. As to the remaining forty-nine states, I have not yet seen any indication(s) of similar statutes. Now please see the following screenshots and links:

One question at hand of course is how well the Massachusetts statute will be enforced. What may be on the books is one thing but what will happen on the road remains to be seen.

I am hopeful.

John Dunn is an electronics consultant, and a graduate of The Polytechnic Institute of Brooklyn (BSEE) and of New York University (MSEE).

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• The headlights and turn signal design blunder
• The dangers of light glare from high-brightness LEDs
• Headlights and turn signals, part two
• LED headlights: Thank goodness for the bright(nes)s

The post Headlights In Massachusetts appeared first on EDN.

Сергій Бойченко: У науці більшість проєктів, що отримують фінансування, повинні мати проривні ідеї, технологічну цінність kpi ср, 07/16/2025 - 16:25

The synthesis of silicon carbide (SiC) requires high temperatures and significant power, posing challenges in reducing the environmental impact of the manufacturing process...

Як народився "РаніоПак": інновація з ароматом хмелю Інформація КП ср, 07/16/2025 - 10:54

Keysight Technologies held its flagship Keysight World Tech Day India on July 8, 2025, at The Leela Palace, Bengaluru, bringing together CXOs, engineers, researchers, and innovators from the electronics and high-tech sectors. The event showcased key technologies shaping the future across multiple industries including telecom, AI, and automotive, offering attendees expert-led sessions, live demonstrations, and in-depth technical tracks designed to accelerate innovation and market readiness in a rapidly evolving technology landscape.

The event also highlighted four key domains shaping the future of technology: 6G and Wireless, AI Infrastructure, Automotive, and AI Networks. Industry experts joined Keysight to explore AI-native 6G networks, THz communication, non-terrestrial networks (NTN), and digital twin-based design for ultra-fast, intelligent connectivity. Experts also discussed advancements in AI infrastructure highlighting compute fabrics, chiplets, optical interconnects, memory, and PCIe Gen7, which are critical enablers of next-gen AI. The automotive segment covered EV battery testing, V2X, autonomous driving, and cybersecurity for smarter mobility and finally AI Networks focused on network emulation, multi-cloud testing, and cybersecurity validation.

Keysight World Tech Day India 2025 brought together professionals from companies working on deep tech offering a unique platform for networking, knowledge sharing, and experiencing next-gen innovations that empower the electronics and high-tech community to stay ahead in a complex ecosystem.

The post Keysight World Tech Day India: Annual Conference Highlights Future-Defining Innovations in 6G, AI, Automotive, and Network Technologies appeared first on ELE Times.

submitted by /u/Linker3000 [link] [comments]

So i have these 230VAC to 5V DC power modules that i took six of and parallel connected the AC side of all six, then i series connected the output of 3 of them 2 times so that I had 2 groups of 3 in series, then i series connected those 2 groups to become this dual rail ±15v Module by using the series connection as ground 0V, negative - on one group became -15V and positive + became +15V. Don't try this if you don't know what you are doing as you can't do this with just any power source and it will burn down your house, zap you, explode possibly harmoni eyes, cause a fire. So don't play with this if you do not know what you are doing. submitted by /u/Whyjustwhydothat [link] [comments]

In collaboration with Gyeonggi-based Wavice Inc, South Korea’s Electronics and Telecommunications Research Institute (ETRI) has developed localization technology for gallium nitride (GaN) monolithic microwave integrated circuits (MMICs) used in transmit/receive modules for military radars and satellites for the first time in Korea using fab-based technology. This is expected to significantly contribute to defense technology self-reliance by enabling the localization of key components not only for military radars but also for high-resolution synthetic aperture radar (SAR) systems...

Integrating ADCs that provide accurate results without requiring a precision integrator capacitor has been around for a long time. A venerable example is that multimeter favorite, the dual-slope ADC. That classic topology uses just one integrator to alternately accumulate both incoming signal and complementary voltage references with the same RC time constant. It thus automatically ratios out time constant tolerance. Slick. 

This Design Idea (DI) will describe a (possibly) new integrating converter that reaches a similar goal of accurate conversions without needing an accurate capacitor. But it gets there via a significantly different route. Along the route, it picks up some advantageous wrinkles.

Wow the engineering world with your unique design: Design Ideas Submission Guide

As Figure 1 shows, the design starts off with an old friend, the 555-analog timer.

Figure 1 Op-amp A1 continuously integrates the incoming Vin signal, thus minimizing noise. Conversion occurs in alternating phases, T- and T+. The T-/T+ phase duration ratio is independent of the RC time constant, is therefore insensitive to C1 tolerance, and contains both Vin magnitude and polarity information.

Incoming signal Vin is summed with the voltage at node X and accumulated by differential integrator A1. A conversion cycle begins when A1’s output (node Y) reaches 4.096 V and lifts timer U1’s threshold pin (Thr) through the R2/R3 divider to the 2.048-V reference supplied by voltage reference Z1. This switches on U1’s Dch pin, grounding A1’s noninverting input through the R4/R5 divider, outputs a zero to the GPIO bit (node Z), and begins the T- phase as A1’s output ramps down. The duration of this T- phase is given by:

T- = R1C1/(1 + Vin/Vfullscale)

Vfullscale = ±2.048v(R1/R6) = ±0.683v

The T- phase ends when A1’s output reaches U1’s trigger (Trg) voltage set to 1.024 V by Z1 and U1’s internal 2:1 divider. See the LMC555 datasheet for the gritty details.

This starts the T+ conversion phase with an output of one on the GPIO bit, and the release of Dch by U1, which drives A1’s noninverting input to 1.024 V, set by Z1 and the R4/R5 divider. The T+ positive-going ramp continues until A1’s output reaches the 4.096 VThr threshold described above and initiates the next conversion cycle. 

T+ phase duration is:

T+ = R1C1/(1 – Vin/Vfullscale)

 This frenetic frenzy of activity is summarized in Figure 2.

Figure 2 Various conversion signals found at circuit nodes X, Y, and Z.

Meanwhile, the GPIO pin is assumed to be connected to a suitable microcontroller counter/time peripheral that is accumulating T- and T+ durations for a chosen resolution and conversion rate. Something between 1 µs and 100 ns should work for the subsequent Vin calculation. This brings up that claim of immunity to integrator capacitor tolerance you might be wondering about.

The durations of the T+ and T- ramps are proportional to C1, as shown in Figure 3.

Figure 3 Black = Vin, Red = T+ duration in ms, Blue = T- duration, C1 = 0.001 µF.

However, software arithmetic saves the day (and maybe even my reputation!) because recovery of Vin from the raw phase duration timeouts involves a bit of divide-and-conquer.

Vin = Vfullscale ((1 – (T-/T+))/(1 + (T-/T+)))

And, of course, when T- is divided by T+, the R1C1 terms conveniently disappear, taking sensitivity to C1 tolerance away with them!

A final word about Vfullscale. The ±0.683 V figure derived above is a minimum value, but any larger span can be easily accommodated by adding one resistor (R8) and changing another (R1). Here’s the scale-changing arithmetic:

R1 = 1M * Vfullscale/0.683

R8 = 1/(1/1M – 1/R1)

 For example, ±10 V is illustrated in Figure 4.

Figure 4 A ±10-V Vin span is easily accommodated – if you can find a 15 MΩ precision resistor.

Note that R1 would probably need to be a series string to get to 15 MΩ using OTS resistors.

Stephen Woodward’s relationship with EDN’s DI column goes back quite a long way. Over 100 submissions have been accepted since his first contribution back in 1974.

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• Adding one resistor improves anemometer analog linearity to better than +/-0.5%
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The post Another weird 555 ADC appeared first on EDN.

Analog designers often need matched resistors for their circuits [1]. The best solution is to buy integrated resistor networks [2], but what can you do if the parts vendors do not offer the desired values or matching grade?

Wow the engineering world with your unique design: Design Ideas Submission Guide

The circuit in Figure 1 can help. It is made of two voltage dividers (a Wheatstone bridge) followed by an instrumentation amplifier, IA, with a gain of 160. R3 is the reference resistor, and R4 is its match. The circuit subtracts the voltages coming out of the two dividers and amplifies the difference.

Figure 1 The intuitive solution is a circuit made of a Wheatstone bridge and an instrumentation amplifier.

Calculations show that the circuit provides a perfectly linear response between output voltage and resistor mismatch (see Figure 2). The slope of the line is 1 V per 1% of resistor mismatch; for example, a Vout of -1 V means -1% deviation between R3 and R4.

Figure 2 Circuit response is perfectly linear with a 1:1 ratio between output voltage and resistor mismatch.

A possible drawback is the price: instrumentation amplifiers with a power supply of ±5 V and more start at about 6.20 USD. Figure 3 shows another circuit using a dual op-amp, which is 2.6 times cheaper than the cheapest instrumentation amplifier.

Figure 3 This circuit also provides a perfect 1:1 response, but at a lower cost.

The transfer function is:

Assuming,

converts the transfer function into the form,

If the term within the brackets equals unity and R5 equals R6, the transfer function becomesIn other words, the output voltage equals the percentage deviation of R4 with respect to R3. This voltage can be positive, negative, or, in the case of a perfect match between R3 and R4, zero.

The circuit is tested for R3 = 10.001 kΩ and R4 = 10 kΩ ±1%. As Figure 4 shows, the transfer function is perfectly linear (the R2 factor equals unity) and provides a one-to-one relation between output voltage and resistor mismatch. The slope of the line is adjusted to unity using potentiometer R2 and the two end values of R4. A minor offset is present due to the imperfect match between R5 and R6 and the offset voltage VIO of the op-amps.  

Figure 4 The transfer function provides a convenient one-to-one reading.

A funny detail is that the circuit can be used to find a pair of matched resistors, R5 and R6, for itself. As mentioned before, it is better to buy a network of matched resistors. It may look expensive, but it is worth the money.

Equation 3 shows that circuit sensitivity can be increased by increasing R7 and/or VREF. For example, if R7 goes up to 402 kΩ, the slope of the response line will increase to 10 V per 1% of resistor mismatch. A mismatch of 0.01% will generate an output voltage of 100 mV, which can be measured with high confidence.

Watch the current capacity of VREF and op-amps when you deal with small resistors. A reference resistor of 100 Ω, for example, will draw 25 mA from VREF into the output of the first op-amp. Another 2.5 mA will flow through R5.

Jordan Dimitrov is an electrical engineer & PhD with 30 years of experience. Currently, he teaches electrical and electronics courses at a Toronto community college.

 Related Content

• Design Notes: Matched Resistor Networks for Precision Amplifier Applications
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• The Effects of Resistor Matching on Common Mode Rejection
• Getting an audio signal with a THD < 0.0002% made easy
• RMS stands for: Remember, RMS measurements are slippery

References

1. Bill Schweber. The why and how of matched resistors (a two part series). https://www.powerelectronictips.com/the-why-and-how-of-matched-resistors-part-1/.
2. Art Kay. Should you use discrete resistors or a resistor network? https://www.planetanalog.com/should-you-use-discrete-resistors-or-a-resistor-network/ .

The post Circuits to help verify matched resistors appeared first on EDN.

Power Integrations Inc of San Jose, CA, USA (which provides high-voltage integrated circuits for energy-efficient power conversion) says that Jennifer A. Lloyd PhD will be its next chief executive officer, succeeding Balu Balakrishnan, who has been CEO since 2002. A former member of Power Integrations’ board of directors, Lloyd has been reappointed to the board. Both appointments are effective from 21 July...

EPC Space LLC of Andover, MA, USA (which provides high-reliability radiation-hardened enhancement-mode gallium nitride-on-silicon transistors and ICs for power management in space and other harsh environments) has announced the EPC7C021 (available now through EPC Space and authorized distributors), a high-performance, three-phase motor demonstration board featuring the radiation-hardened EPC7011L7C eGaN IC. Designed for ease of evaluation and system integration, the EPC7C021 delivers a user-friendly, flexible platform for developing motor drive applications such as reaction and momentum wheels, ion thrusters, robotics and other automation in demanding radiation environments...