Improving the Reload2 active load
Introduction
With another colleague at work, we are currently developing an electronic board that will eventually be powered over Ethernet. To gain more experience with this technology, we prototyped a standalone power supply stage.
We want to test this stage with different load profiles. While we already have professional grade active loads at work, I had previously read about the Reload2 product from Arachnidlabs, a low cost active load sold on Hackaday:
OOKLONE: a cheap RF 433.92MHz OOK frame cloner
Fabien Le Mentec built a pocket device that listens to and clones 433.92MHz OOK frames, automating the tedious reverse engineering of cheap wireless outlets. The prototype uses a Moteino with an RFM69 to sample demodulated OOK data, stores pulse durations in SRAM, and replays frames; the code and hardware notes are available on GitHub along with limitations and next steps.
Practical protection against dust and water (i.e. IP protection)
Needing IP65 protection while exposing humidity and pressure sensors on a tight $15 budget, Dr Cagri Tanriover hunted for a practical fix. He found that an SHT2x humidity sensor with a microporous filter cap and O-ring provides IP67-level protection, and by matching a pressure sensor that fits the same cap he met and exceeded the IP65 requirement. The post shows a low-cost, component-level workaround.
A wireless door monitor based on the BANO framework
Fabien Le Mentec built a battery-powered wireless door monitor and a reusable node framework called BANO to monitor doors across seven floors without wired links. The post highlights BANO's 17-byte key,value protocol, the node runtime that enables wake-on-interrupt low-power operation, and practical RF choices like the NRF905 plus a 330 µF cap to handle coin-cell transmission peaks. It includes source, PCB, and base station notes.
Using the Beaglebone PRU to achieve realtime at low cost
Fabien Le Mentec shows how the BeagleBone Black's PRU coprocessors can run hard realtime control loops, removing the need for an FPGA or dedicated microcontroller. He walks through Linux setup, device tree enabling, assembler and loader tools, and a timer example that reads ADCs and drives PWM from PRU code. The post highlights community SDKs and a recent TI Code Composer Studio option for C-based PRU development.
A simple working I2C (TWI) level shifter
When interfacing 3.3V and 5V boards, Dr Cagri Tanriover shows a no-fuss MOSFET solution to keep I2C talking across voltages. The post walks through using the NXP MOSFET level-shifter idea with BS170 transistors and 10 kΩ pull-ups, notes it ran at 400 kbps for his setup, and includes a quick four-step test to verify the build before connecting microcontrollers.
Requirements, Specifications and Tests
A practical workflow keeps embedded projects predictable and reduces late surprises. Start with a client-driven Set of Requirements, then derive a QA Test Set from those requirements, and write a Technical Spec that maps to the design. The method enforces change control, helps catch feature creep early, and makes final acceptance straightforward for non-engineer testers.
Layout recomendations and tips for best performance against EMC
Good PCB layout will prevent many EMC headaches before you even power the board. Maykel Alonso offers a practical checklist covering component and feed analysis, package and PCB choices, placement, routing, and via rules. The post focuses on concrete, low-effort measures like preferring SMD parts, using a 4-layer FR-4 stack with dedicated ground and power planes, and keeping return paths tight to cut emissions and susceptibility.
First Steps in OrCAD 16 [Capture]
A practical, beginner-friendly walkthrough of OrCAD 16 Capture that gets you from a blank project to a netlist ready for PCB layout. Maykel explains the OrCAD suite, project tree and design cache behavior, how to manage part libraries, and the Tools menu utilities you should run. The article ends with step-by-step instructions for creating the .mnl netlist and previews a follow-up on layout and footprint libraries.
Using XML to describe embedded devices (and speak to them)
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Review: Prototype to Product
Alan Cohen's Prototype to Product is a practical systems engineering playbook for anyone taking an embedded idea to market. The review emphasizes uncovering surprises early, disciplined planning, and cross-discipline collaboration across electrical, mechanical, software, and manufacturing domains. It highlights concrete topics such as prototyping, DFM/DFA, staged testing, and regulatory considerations that help avoid costly late-stage rework.
3 Overlooked Embedded Software Elements
Jacob Beningo points out three often-overlooked elements that can make embedded projects less painful and faster to ship. He highlights model-generated code for off-target iteration, configuration-generated code to manage SKUs and avoid fragile conditional compilation, and automated test harnesses to catch regressions early. The post gives practical reasons to consider each approach and how they fit into modern embedded DevOps.
VolksEEG Project: Initial Hardware Architecture
The VolksEEG prototype pairs an Adafruit Feather nRF52840 Sense MCU with an ADS1299 analog front end, organized into non-isolated and isolated domains to protect patients. The post explains why isolation is required, which chips bridge the domains, and why simple, high-level power and signal diagrams help clarify the KiCad schematics for engineers and reviewers.
Practical protection against dust and water (i.e. IP protection)
Needing IP65 protection while exposing humidity and pressure sensors on a tight $15 budget, Dr Cagri Tanriover hunted for a practical fix. He found that an SHT2x humidity sensor with a microporous filter cap and O-ring provides IP67-level protection, and by matching a pressure sensor that fits the same cap he met and exceeded the IP65 requirement. The post shows a low-cost, component-level workaround.
Introducing The VolksEEG Project
VolksEEG is an open-source effort to build an FDA-cleared clinical EEG and publish every design so others can manufacture it. The volunteer-driven project centers on the TI ADS1299 8-channel, 24-bit biopotential ADC and combines medical and electrical engineering expertise to confront regulatory, safety, and usability challenges. This blog series will document technical decisions, isolation and safety concerns, and ways engineers can contribute.
Improving the Reload2 active load
IntroductionWith another colleague at work, we are currently developing an electronic board that will eventually be powered over Ethernet. To gain more experience with this technology, we prototyped a standalone power supply stage.
We want to test this stage with different load profiles. While we already have professional grade active loads at work, I had previously read about the Reload2 product from Arachnidlabs, a low cost active load sold on Hackaday:
Off the shelf availability of Custom IoT Gateway
Choosing the right gateway can make or break an IoT deployment, yet industrial gateways are often expensive and generic. This post walks through practical criteria for off-the-shelf and custom gateways, covering edge computing trade-offs, mainframe versus embedded Linux, SoC and ADC choices, interfacing and debugging needs, and when to design your own hardware for real-time or protocol demands.
Make Your Own MCU Boards (2023 Teardown Conference)
Ditch the development boards! Products like the Nucleo development boards serve a wonderful purpose, but they’re ill-suited for projects that need to be small and cheap, such as hobby projects or products just beginning a production run. In this talk (a recording from the 2023 Teardown Conference), you’ll learn how to put a microcontroller or other custom circuit on a PCB a little larger than a stick of gum for less than $3 a board.
First Steps in OrCAD 16 [Capture]
A practical, beginner-friendly walkthrough of OrCAD 16 Capture that gets you from a blank project to a netlist ready for PCB layout. Maykel explains the OrCAD suite, project tree and design cache behavior, how to manage part libraries, and the Tools menu utilities you should run. The article ends with step-by-step instructions for creating the .mnl netlist and previews a follow-up on layout and footprint libraries.
The Teardown Conference Call for Proposals is Open for Another Week!
The Teardown conference "Call for Proposals" goes until Wednesday, January 15th! Get yours in soon!
Practical protection against dust and water (i.e. IP protection)
Needing IP65 protection while exposing humidity and pressure sensors on a tight $15 budget, Dr Cagri Tanriover hunted for a practical fix. He found that an SHT2x humidity sensor with a microporous filter cap and O-ring provides IP67-level protection, and by matching a pressure sensor that fits the same cap he met and exceeded the IP65 requirement. The post shows a low-cost, component-level workaround.
Getting Started With CUDA C on an Nvidia Jetson: GPU Architecture
In the previous blog post (Getting Started With CUDA C on Jetson Nvidia: Hello CUDA World!) I showed how to develop applications targeted at a GPU on a Nvidia Jetson Nano. As we observed in that blog post, performing a calculation on a 1-D array on a GPU had no performance benefit compared to a traditional CPU implementation, even on an array with many elements. In this blog post, we will learn about the GPU architecture to better explain the behavior and to understand the applications where a GPU shines (hint: it has to do with graphics).
How to Design Reliable Reset Circuits for Embedded Microcontrollers
In the world of embedded systems, the reset circuit is a critical component that ensures the microcontroller starts up correctly and recovers gracefully from unexpected events like power fluctuations or software crashes. A poorly designed reset circuit can lead to erratic behavior, system lockups, or even permanent damage to the microcontroller. For embedded engineers, designing a reliable reset circuit is essential for ensuring the stability and robustness of the system.
Better Hardware Design Decisions, Faster: A Lean Team’s Guide to MDO
As design complexity grows, siloed decision-making often leads to late-stage surprises, costly rework, and missed opportunities for optimization. Multidisciplinary Design Optimization (MDO) offers a structured approach to solving this by enabling teams to evaluate trade-offs and impacts across the full system before implementation begins. Traditionally used in large, high-budget industries like aerospace, MDO is now within reach for lean teams, thanks to more accessible modeling tools and an urgent need for tighter collaboration. This article outlines how small hardware teams can adopt MDO in a practical way, starting simple, integrating key models early, and building toward a culture of systems thinking. The result is better design decisions, faster development, and more robust, manufacturable products with fewer surprises along the way.
VolksEEG Project: Initial Hardware Architecture
The VolksEEG prototype pairs an Adafruit Feather nRF52840 Sense MCU with an ADS1299 analog front end, organized into non-isolated and isolated domains to protect patients. The post explains why isolation is required, which chips bridge the domains, and why simple, high-level power and signal diagrams help clarify the KiCad schematics for engineers and reviewers.
Software Prototyping
In my recent blog entry on the product development process (way down, near the end of the entry), I wrote the following:
"I continue these sorts of tests, building more and more complexity, until I am satisfied that my circuit is basically functional. Then, using the test code that I have created as a model, I begin to write the real software for my product. As my software grows, to complete the full functionality of my design, I sometime find it useful to drop back to my 'test software'...
Layout recomendations and tips for best performance against EMC
Good PCB layout will prevent many EMC headaches before you even power the board. Maykel Alonso offers a practical checklist covering component and feed analysis, package and PCB choices, placement, routing, and via rules. The post focuses on concrete, low-effort measures like preferring SMD parts, using a 4-layer FR-4 stack with dedicated ground and power planes, and keeping return paths tight to cut emissions and susceptibility.
Size matters - System success depends on initial design
A seemingly small UI choice can reshape an entire embedded system. Gene Breniman uses a real product example to show how picking a graphic touchscreen instead of a character LCD can multiply CPU, memory, OS, and licensing needs. The post explains why capturing requirements early and planning for growth paths keeps complexity and cost under control, and how to size hardware to fit real needs.
Bringing up Baby - product development thoughts
Things have just started to get exciting. After months of defining, specifying and designing my latest product, I finally have semi-functional prototypes. After a few side steps during the building and bring-up process, power is applied and most of the low level functions have been verified. Soon, software will meet hardware and debugging can begin in earnest.
Before jumping in and really enjoying the fun (besides I'm now waiting for some new parts to arrive), I thought it would be nice to...
Review: Prototype to Product
Alan Cohen's Prototype to Product is a practical systems engineering playbook for anyone taking an embedded idea to market. The review emphasizes uncovering surprises early, disciplined planning, and cross-discipline collaboration across electrical, mechanical, software, and manufacturing domains. It highlights concrete topics such as prototyping, DFM/DFA, staged testing, and regulatory considerations that help avoid costly late-stage rework.
