Innovation is critical in today’s engineering world and it demands technical knowledge and the highest level of creativity. Seeing compact articles that solve design problems or display innovative ways to accomplish design tasks can help to fuel your electronics creativity.
You can find many very circuit ideas at ePanorama.net circuits page.
In addition to this links to interesting electronics design related articles worth to check out can be posted to the comments section.
1,778 Comments
Tomi Engdahl says:
Marx Generator
http://www.penguinslab.com/marx.htm
Tomi Engdahl says:
Keep your drone flying high with the right circuit protection design
https://www.edn.com/design/analog/4461744/Keep-your-drone-flying-high-with-the-right-circuit-protection-design?utm_content=buffer023b1&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Tomi Engdahl says:
Passive filter cleans up power-line communications
https://www.edn.com/5G/4337469/Passive-filter-cleans-up-power-line-communications?utm_content=bufferf19c2&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Tomi Engdahl says:
Design PCBs for EMI, part 2: Basic stack-up
https://www.edn.com/electronics-blogs/the-emc-blog/4461714/Design-PCBs-for-EMI–part-2–Basic-stack-up?utm_content=buffer80188&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Tomi Engdahl says:
Find a signal’s bandwidth from its harmonics
Bob Witte -March 18, 2019
https://www.edn.com/electronics-blogs/fun-with-fundamentals/4461711/Find-a-signal-s-bandwidth-from-its-harmonics?utm_content=buffer2c0cd&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Tomi Engdahl says:
Why Have an Air Gap?
https://www.powerelectronics.com/content/why-have-air-gap?PK=UM_Classics04119&utm_rid=CPG05000002750211&utm_campaign=24648&utm_medium=email&elq2=bae2aeab5e6c4da0a72f41f46fbaf2a0
What exactly is the function of the air gap? When asked this question, most engineers respond, “It prevents core saturation.” Although this may be true in certain cases, it’s not true in general. In fact, in a transformer, the air gap will not prevent saturation caused by excessive ac voltage polarization, as we will see. Further, the air gap has several other critical functions.
Tomi Engdahl says:
What’s All This T-Coil Stuff, Anyhow?
https://www.electronicdesign.com/analog/what-s-all-t-coil-stuff-anyhow?NL=ED-003&Issue=ED-003_20190405_ED-003_360&sfvc4enews=42&cl=article_1_b&utm_rid=CPG05000002750211&utm_campaign=24657&utm_medium=email&elq2=66d3a6b3b204415e82e2cbd2cb7522c0
Adding a T-coil inductor and capacitor combo to your amplifier will extend its bandwidth. These circuits are also useful in high-speed digital I/O and video distribution.
A T-coil uses a coupled inductor, essentially a transformer with three leads. It can double amplifier bandwidth, and the bridging capacitor gives it a constant input impedance.
Tomi Engdahl says:
Millimeter-Wave Sensors Enhance Factory Safety
https://www.electronicdesign.com/industrial-automation/millimeter-wave-sensors-enhance-factory-safety?NL=ED-005&Issue=ED-005_20190410_ED-005_195&sfvc4enews=42&cl=article_1_b&utm_rid=CPG05000002750211&utm_campaign=24756&utm_medium=email&elq2=c527d63e77f04ac99cffb11b96b63920
When you think of a sensor, you probably don’t think of millimeter-wave (mmWave) radar. Now, though, you can add mmWave radar chips to your mental archive along with the other more traditional sensors. If you’re designing new systems requiring proximity detection and the presence and movement of people, these radar ICs just may be a solution to consider.
Tomi Engdahl says:
Home> Analog Design Center > How To Article
Understanding the basics of setup and hold time
https://www.edn.com/design/analog/4371393/Understanding-the-basics-of-setup-and-hold-time?utm_content=buffer0b348&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Tomi Engdahl says:
The pitfalls of power-rail noise measurements
https://www.edn.com/design/test-and-measurement/4461743/The-pitfalls-of-power-rail-noise-measurements?utm_content=buffer41d22&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Tomi Engdahl says:
Signal integrity analysis of a #BeagleBone Black reveals how designers could violate #design rules to cut costs & still produce a working #board Mentor Graphics BeagleBoard.org Foundation #DDR3 #microcontroller #engineering #maker https://buff.ly/2UqNkCI
Low-cost design: When best practice is too expensive
https://www.edn.com/design/test-and-measurement/4461787/Low-cost-design–When-best-practice-is-too-expensive?utm_content=buffer0b884&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer
Tomi Engdahl says:
Ultrasound: Don’t Be Blinded by Your Amplifier’s Slow Overload Recovery
https://www.electronicdesign.com/analog/ultrasound-don-t-be-blinded-your-amplifier-s-slow-overload-recovery?NL=ED-003&Issue=ED-003_20190411_ED-003_764&sfvc4enews=42&cl=article_2_b&utm_rid=CPG05000002750211&utm_campaign=24814&utm_medium=email&elq2=57bcb54a94954afca6443ca00551369c
Developing an ultrasound receiver with good overload recovery characteristics can greatly simplify HW/SW design and debug challenges, speeding up time-to-market and considerably enhancing image quality.
Ultrasound receivers are frequently exposed to overload conditions during B-mode and pulsed Doppler operation. These conditions can saturate the amplifiers and/or the analog-to-digital converter (ADC) within the receive amplifier-front-end (AFE) signal chain. An ultrasound receiver with poor overload recovery characteristics can greatly complicate design, significantly reduce image quality, and lengthen time-to-market. This article reviews ultrasound system design challenges with regard to overload recovery, and presents a new approach to address this issue.
Tomi Engdahl says:
Low Power Meets Variability At 7/5nm
https://semiengineering.com/low-power-meets-variability-at-7-5nm/
Reductions in voltage, margin and increases in physical effects are making timing closure and signoff much more difficult.
Tomi Engdahl says:
Single-sideband demodulator covers the HF band
https://www.edn.com/design/analog/4358621/Single-sideband-demodulator-covers-the-HF-band?utm_content=buffer73e69&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
The modulator employs a phasing network to split a low-frequency audio signal into in-phase and quadrature (orthogonal) components. This circuit delivers a phase error of only 0.15° and has a low sensitivity to component tolerances, which are advantages over other phasing circuits (Reference 1). By reversing the direction of the network, that is, feeding the output with two orthogonal signals and tapping the input, the network functions as a detector.
Tomi Engdahl says:
Design PCBs for EMI, part 3: Partitioning and routing
https://www.edn.com/electronics-blogs/the-emc-blog/4461793/Design-PCBs-for-EMI-part-3-Partitioning-and-routing-?utm_content=buffer002bc&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Tomi Engdahl says:
Digital potentiometer simulates log taper to accurately set gain
https://www.edn.com/design/analog/4461777/Digital-potentiometer-simulates-log-taper-to-accurately-set-gain?utm_content=bufferd0e2a&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Imagine, for example, an amplifier with gain that you set over a range of 0 to 10,000 (80dB) using an 8-bit (1 in 256) resolution pot. With a linear relationship between potentiometer setting and resistance (linear taper) there will be a linear relationship between dpot setting and gain. One step in each of the 256 pot settings represents a gain change increment of roughly 40 (i.e., gain steps will be 0, 40, 80, 120, 160, etc.).
Tomi Engdahl says:
LVDT: Linear Variable Differential Transformer – Inductive Sensors
https://www.electricaltechnology.org/2019/04/lvdt-linear-variable-differential-transformer.html
Tomi Engdahl says:
Film capacitors: Characteristics and uses in power applications
https://www.edn.com/design/power-management/4461814/Film-capacitors–Characteristics-and-uses-in-power-applications-?utm_content=buffer475db&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer
Tomi Engdahl says:
Understanding System Protection: What You Don’t Know Might Hurt Your System
https://www.electronicdesign.com/analog/understanding-system-protection-what-you-don-t-know-might-hurt-your-system?NL=ED-003&Issue=ED-003_20190429_ED-003_303&sfvc4enews=42&cl=article_1_b&utm_rid=CPG05000002750211&utm_campaign=25180&utm_medium=email&elq2=a9e1f80ee958485e9191ffcf2c178f5c
Certain types of electrical stresses, if ignored, can lead to component damage and ultimately bring down a system. What makes for an effective protection scheme, and how do you avoid the pitfalls when implementing it?
Tomi Engdahl says:
Simulation Domain Transformation Between Time and Frequency
https://www.mwrf.com/software/simulation-domain-transformation-between-time-and-frequency?Issue=MWRF-001_20190430_MWRF-001_552&sfvc4enews=42&cl=article_1_b&utm_rid=CPG05000002750211&utm_campaign=25217&utm_medium=email&elq2=5f24b0f5e1d04fcdba211c810b2ac2f7
Thanks to its fast Fourier transform process, a software tool can convert data between the frequency domain and time domain.
Tomi Engdahl says:
Decibels: Use with caution
https://www.edn.com/electronics-blogs/fun-with-fundamentals/4461810/Decibels–Use-with-caution?utm_source=newsletter&utm_campaign=link&utm_medium=EDNWeekly-20190425
Tomi Engdahl says:
Film capacitors: Characteristics and uses in power applications
https://www.edn.com/design/power-management/4461814/Film-capacitors–Characteristics-and-uses-in-power-applications-?utm_source=newsletter&utm_campaign=link&utm_medium=EDNWeekly-20190502
Engineers designing power electronics find that capacitors are needed for several functions, from energy storage to filters and decoupling. Different capacitor types are available, that at first sight might seem equivalent in their headline ratings of capacitance and voltage, but would not perform equally. Incorrect selection can lead to, at best, an expensive ‘over-engineered’ solution and, at worst, an unreliable or unsafe product.
This article describes the different types of capacitors that might be considered for use in power electronics applications. Particularly, electrolytic and film types are compared showing how and when each has a role. The variety of film types and their construction are described in more detail and preferred types identified. Specifications for capacitance, ripple current rating, transient voltage immunity, and safety rating, along with other characteristics are examined in detail.
Tomi Engdahl says:
How to Read Data Sheets: Logic Timing (Part 4)
https://www.eeweb.com/profile/elizabeth-simon/articles/how-to-read-data-sheets-logic-timing-part-4
Tomi Engdahl says:
EEVblog #1208 – Circuit Analysis & Debugging
https://www.youtube.com/watch?v=x0Dk5SSCMZo
Dave answers a beginner forum question of why their 74HC390 based breadboard counter circuit does not work properly.
Let’s get up to our armpits in datasheets and troubleshooting.
A two sentence forum response turned into a step-by-step 27min video investigation involving rise and fall times, setup and hold times, metatability, optocouplers, bypassing, open collectors, and breadboard connector traps for young players.
Tomi Engdahl says:
Current-Sense Amplifiers from A to “I”
https://www.electronicdesign.com/power/current-sense-amplifiers-i?code=NN8DK04&utm_rid=CPG05000002750211&utm_campaign=25273&utm_medium=email&elq2=5da4a6fec8524c359f3dfe04f6edcdf7
Sponsored by Digi-Key and Texas Instruments: What are the best ways to measure current flow? It often comes down to the application at hand—this article discusses some of the pros and cons of some of these methods.
Accurately measuring current flow is a standard requirement in several applications (Fig. 1). Depending on the specific need, the options available to designers can include discrete designs assembled from standard components, application-specific devices, and ready-made solutions embedded into another block such as a microcontroller or system-on-chip (SoC) device. In this article, we’ll look at some of these approaches, their advantages and disadvantages, and how to make the best use of them in a design.
Tomi Engdahl says:
Engineer It: How to Design Protection Circuits for Analog I/O Modules
https://www.youtube.com/watch?v=f2Xl0qN17zQ
Learn how to design protection circuits for analog input/output (I/O) modules. The video explains how attenuation and diversion can help you protect your system — especially when used together.
Tomi Engdahl says:
Break Design Rules and Get Away with It
https://www.eeweb.com/profile/martin-rowe-2/articles/break-design-rules-and-get-away-with-it
That’s what the designers of the BeagleBone Black did. They had to keep costs exceptionally low, and simulation revealed the corners they cut while still producing a functional board.
Every engineer must design circuits and systems that meet budget constraints and quality requirements. With consumer and maker/hobbyist product design, every cent counts. One extra part — even a resistor — can make a difference when a board will be produced by the millions. If your product can’t meet the selling price that the market will bear, the game is over.
That’s the predicament faced by the designers of low-cost products such as the BeagleBone, Adruino, Raspberry Pi, and other microcontroller boards for the hobby and maker markets.
Tomi Engdahl says:
Hybrid protection devices combine a GDT and MOV in a single package
https://www.electronicproducts.com/Passive_Components/Circuit_Protection/Hybrid_protection_devices_combine_a_GDT_and_MOV_in_a_single_package.aspx?utm_content=bufferf1562&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
Bourns’s integrated FLAT gas discharge tube (GDT) technology with a metal oxide varistor (MOV) solves the limitations of using MOVs alone
Tomi Engdahl says:
µModule isolators offer 7.5kV isolation for industrial and automotive systems
https://www.electropages.com/2019/05/module-isolators-offer-75kv-isolation-industrial-and-automotive-systems?utm_campaign=2019-05-23-Electropages-Email-Newsletters&utm_source=newsletter&utm_medium=email&utm_term=article&utm_content=%C2%B5Module+isolators+offer+7.5kV+isolation+for+industrial+and+automotive+systems
Mouser now offers the Power by Linear LTM2810 µModule isolators from Analog Devices. Giving up to 7.5kVRMS of isolation, the isolators are ideal for test and measurement equipment, medical equipment, EV and HEV systems, industrial applications, and metering systems.
The µModule isolators provide separate logic supply pins, supporting easy interfacing with different logic levels ranging from 1.6V to 5.5V. The devices coupled isolators are powered on each side by 3V to 5.5V supplies and give 7.5kVRMS of isolation for one minute between the input and output logic interface.
The µModule isolators offer an integrated transformer driver on the logic side and a LDO regulator on the isolated side, regulating the rectified transformer output.
Tomi Engdahl says:
The Benefits of Opto-Coupled and Digital Isolators in Circuit Design Today
http://www.electronics-know-how.com/article/2778/the-benefits-of-opto-coupled-and-digital-isolators-in-circuit-design-today
There are many challenges in circuit design today and understanding the key differences between digital isolators and opto-coupled isolators in circuit design helps developers design more effectively. This whitepaper reviews the challenges of modern circuit design, industry design trends, the use of various isolators, such as CMOS digital isolators, and the benefits of each.
Tomi Engdahl says:
Controlling Variability And Cost At 3nm And Beyond
https://semiengineering.com/controlling-variability-and-cost-at-3nm-and-beyond/
Lam’s CTO talks about how more data, technology advances and new materials and manufacturing techniques will extend scaling in multiple directions.
Tomi Engdahl says:
Evolution Of Verification Engineers
https://semiengineering.com/evolution-of-verification-engineers/
Experts at the Table, part 3: The role of a verification engineer will change and start to look a lot like knowledge management.
Tomi Engdahl says:
High-voltage current sensing with low-voltage transistors
https://www.edn.com/design/analog/4461905/High-voltage-current-sensing-with-low-voltage-transistors?utm_source=newsletter&utm_campaign=link&utm_medium=EDNWeekly-20190530
Current monitoring has become simpler because of the availability of dedicated integrated circuits. Current monitoring integrated circuits are readily available and under most circumstances do an excellent job, as do various instrumentation amplifiers, so building a current monitor using discrete devices may seem redundant, however there are circumstances where a circuit using discrete components might be the best approach especially if readily available low voltage parts can be used.
The circuit in this Design Idea resulted from the need to monitor current in both rails of a servo system’s +180/−180V power supply.
Inspiration for this circuit and all those that use this topology derives from the current mirror topology
Tomi Engdahl says:
Characterize DC-DC converter EMI with near-field probes
https://www.edn.com/electronics-blogs/the-emc-blog/4461902/Characterize-DC-DC-converter-EMI-with-near-field-probes?utm_source=newsletter&utm_campaign=link&utm_medium=EDNWeekly-20190530
EMI from on-board DC-DC converters is a common problem with IoT products. These small circuits generally switch between 1 MHz and 3 MHz and use very fast sub-nanosecond edge speeds. The result is broadband EMI often extending above 2 GHz. This EMI can affect the sensitivity of sensitive receiver circuits, especially cellular and Global Navigation Satellite System (GNSS).
One useful way to characterize the EMI performance of a DC-DC converter is to measure the rise time and ringing using a small H-field probe in the time domain. This may be done non-invasively by coupling an H-field probe to the converter output inductor
Tomi Engdahl says:
Medical safety standards in power supplies
https://www.edn.com/electronics-products/electronic-product-reviews/other/4461959/Medical-safety-standards-in-power-supplies
Medical power supplies can be dangerous to patients and users if not properly designed and rated by a valid safety organization.
One such standard that applies to medical electronic equipment is ANSI/AAMI ES60601-1:2005, Part 1.
The new parts, PMM15, PMM20, and PMM30, are certified to the 3rd Edition of the IEC/EN/ANSI/AAMI ES 60601-1 medical safety standard (some call this the “bible” of medical electrical equipment standards).
With a clearance and creepage distance of 8mm, a typical leakage current of 2μA and a 5,000VAC isolation voltage.
Medical equipment must be designed to guarantee the highest level of safety up to 5,000 meters.
3rd Edition of the IEC/EN/ANSI/AAMI ES 60601-1 medical safety standard
http://www.aami.org/productspublications/ProductDetail.aspx?ItemNumber=1578
Tomi Engdahl says:
Simple technique makes low-cost pc-board shields
https://www.edn.com/design/analog/4333661/Simple-technique-makes-low-cost-pc-board-shields
Tomi Engdahl says:
Home> Analog Design Center > Design Idea
High-voltage current sensing with low-voltage transistors
https://www.edn.com/design/analog/4461905/High-voltage-current-sensing-with-low-voltage-transistors
Tomi Engdahl says:
Home> Community > Blogs > The EMC Blog
Characterize DC-DC converter EMI with near-field probes
https://www.edn.com/electronics-blogs/the-emc-blog/4461902/Characterize-DC-DC-converter-EMI-with-near-field-probes
Tomi Engdahl says:
Stanford’s Pinpoint Is a Novel Tool for In-Circuit PCB Debugging
https://blog.hackster.io/stanfords-pinpoint-is-a-novel-tool-for-in-circuit-pcb-debugging-c433a56f140d
Tomi Engdahl says:
https://www.edn.com/design/power-management/4461911/Temperature-compensated-lead-acid-battery-float-charger
Tomi Engdahl says:
Home> Power-management Design Center > Design Idea
Lowering quiescent current by a factor of 4 in an electronic latching switch
https://www.edn.com/design/power-management/4462063/Lowering-quiescent-current-by-a-factor-of-4-in-an-electronic-latching-switch
Tomi Engdahl says:
High-voltage current-feedback amplifier is speedy
https://www.edn.com/design/analog/4354429/High-voltage-current-feedback-amplifier-is-speedy
Tomi Engdahl says:
https://spectrum.ieee.org/at-work/education/you-dont-need-sight-to-read-these-electronic-schematics
Tomi Engdahl says:
Debugging approach for resolving noise issues in a PDN
https://www.edn.com/design/power-management/4462018/Debugging-approach-for-resolving-noise-issues-in-a-PDN
Tomi Engdahl says:
This Tiny $10 Device Can Perform NFC Payment Replay Attacks
https://blog.hackster.io/this-tiny-10-device-can-perform-nfc-payment-replay-attacks-5486d6ecc405
Tomi Engdahl says:
Electronic Eye Circuit – Using LDR and IC 4049 For Security Control
https://www.electricaltechnology.org/2019/07/electronic-eye-circuit.html
Tomi Engdahl says:
Measure humidity with an RH bridge and digitally-programmable capacitor
https://www.edn.com/design/test-and-measurement/4462064/Measure-humidity-with-an-RH-bridge-and-digitally-programmable-capacitor
An AC bridge circuit can be used to measure the unknown capacitance of a sensor, such as a relative humidity (RH) sensor. Some RH sensors have a transfer function of capacitance vs %RH.
Using the NCD2400 digitally programmable capacitor array with high step resolution can help determine the value of the unknown capacitance and the RH using a standard AC bridge circuit.
The NCD2400 is an I2C controlled device in a tiny DFN package that offers a wide capacitance range and non-volatile operation with 512-state digital capacitor states. Data is written to it over a standard I2C 2-wire bus.
Tomi Engdahl says:
Home> Pc-board Design Center > How To Article
Optimize solder stencil aperture to increase connector options
https://www.edn.com/design/pc-board/4462091/Optimize-solder-stencil-aperture-to-increase-connector-options
As electronic systems increase in component density, designers will typically look to match fine 0.10 mm thick solder paste stencils on the pc board to equally fine connectors with a co-planarity not in excess of 0.10 mm. However, a connector co-planarity value of 0.15 mm is not uncommon and it gets increasingly difficult to achieve 0.10 mm as the number of connector pins increases and with formed-pin, right-angle connectors. This has restricted designers’ connector options
However, a study by Samtec Inc. and Phoenix Contact has shown that by optimizing the solder stencil aperture, designers can use the more widely available and less expensive 0.15 mm co-planarity connectors with the finer 0.10 mm stencils, while still meeting IPC-J-STD-001 Class 2 criteria for a 100% yield.
Tomi Engdahl says:
Digital potentiometer simulates log taper to accurately set gain
https://www.edn.com/design/analog/4461777/Digital-potentiometer-simulates-log-taper-to-accurately-set-gain
Digital potentiometers (dpots) are ubiquitous components available in a variety of packages, resistances, and resolutions. However, few implement anything but the usual linear function of resistance vs. setting. This fact makes trouble for applications that need a wide (i.e., multiple decades) dynamic range of gain adjustment.
But all is not lost. The Design Idea presented in Figure 1 implements an approximate logarithmic gain control with an ordinary linear-taper pot (e.g., ADI’s inexpensive bipolar AD5200).
That gain-setting resolution remains no worse than 1dB over the entire 60dB =1,000-to-1 range is especially significant. Additionally, Dx =0 sets a gain of zero while Dx = 255 selects open-loop.
If better than 8-bit (1/256) resolution is desired, parts like the 10-bit AD5292 can be dropped into the topology for 4× higher gain setting precision.
Tomi Engdahl says:
How To Measure DC Amps With a Clamp Meter
https://housetechlab.com/how-to-measure-dc-amps-with-a-clamp-meter/
most clamp meters are built to measure only alternating currents, just a few measure direct current