Category Archives: Aggregated

App note: Practical considerations of Trench MOSFET stability when operating in linear mode

via Dangerous Prototypes


Practical considerations of Trench MOSFET stability when operating in linear mode, application note (PDF!) from Fairchild Semiconductor

This application note focuses on the factors affecting the thermal instability condition of a trench MOSFET device in Linear Mode. In particular, it studies the phenomenon when the drain current (Id) focusing process occurs that leads to a localized hot spot to the device. Several devices were tested to failure to determine the degree of damage within the die and to differentiate the failure signatures under diferent test conditions. The practical analysis of the device Forward-Biased Safe Operating Area (FBSOA) performance in Linear Mode is presented. It is evaluated in terms of finding the Zero Temparature Coefficient (ZTC) value of the device based on its Id vs. Vgs performance characteristic curves.

Free PCB coupon via Facebook to 2 random commenters

via Dangerous Prototypes


Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • We’ll contact you via Facebook with a coupon code for the PCB drawer.
  • Limit one PCB per address per month, please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

RadarCat Gives Computers A Sense of Touch

via hardware – Hackaday

So far, humans have had the edge in the ability to identify objects by touch. but not for long. Using Google’s Project Soli, a miniature radar that detects the subtlest of gesture inputs, the [St. Andrews Computer Human Interaction group (SACHI)] at the University of St. Andrews have developed a new platform, named RadarCat, that uses the chip to identify materials, as if by touch.

Realizing that different materials return unique radar signals to the chip, the [SACHI] team combined it with their recognition software and machine learning processes that enables RadarCat to identify a range of materials with accuracy in real time! It can also display additional information about the object, such as nutritional information in the case of food, or product information for consumer electronics. The video displays how RadarCat has already learned an impressive range of materials, and even specific body parts. Can Skynet be far behind?

Again, this could provide robots with a sense of touch, in a manner of speaking, that rivals our own human capacity for object recognition. This has applications for a wide range of robots: industrial machines will be able to recognize the material composition of an object that may require more force to lift while wearable versions would assist humans with disabilities. This is a technology worth keeping an eye on.

While this tech is a ways away from widespread use, you can still turn anything into a touch sensor today with Touché.

[via /r/linux]

Filed under: hardware, Software Development

Friday Product Post: I Feel the Need. The Need for CEED!

via SparkFun Electronics Blog Posts

To be honest, the word play was too good to resist on today’s product post. Hello, everyone, and welcome to a new Friday Product Post. We have another big week for you today! The new pi-topCEED is now available, as well as two APA102 LED strips and a beefy 48-Segment LED bar graph. Enough dawdling; let’s take a look at what we have!

With this pi-top, you too can sucCEED

Pi-TopCEED (Green)

$ 114.95

The pi-topCEED is a DIY desktop computer that helps you start learning how to code, create awesome devices and take your knowledge to the next level. This Raspberry Pi-powered computer is an excellent resource to any budding hobbyist, student or intrigued user wanting to learn more about the capabilities of the credit card-sized development board. The only things this kit doesn’t include are its own Raspberry Pi, keyboard, mouse and speakers; you’ll need to supply those on your own. We purposefully chose the pi-topCEED without its own RPi due to the fact that most of you already own your own board and may not want to use a different or more expensive one.

Pi-TopCEED (Gray)

$ 114.95

Green not your color? No worries! If you are looking to get a new pi-topCEED, we also offer it in gray! This Raspberry Pi-powered desktop computer is identical in every way to its sibling above, apart from the color.

Remember neither pi-topCEED comes with a Raspberry Pi. If you need one, be sure to pick one up here!

LED RGB Strip - Addressable, 1m (APA102)

$ 15.95

These are addressable 1-meter-long 5V RGB LED strips that come packed with 60 APA102Cs. APA102 LEDs are very similar to WS2812s with a few caveats: APA102s can be controlled with a standard SPI interface, and they have an extremely high PWM frequency. There is access to each APA102 LED, and each strip length can be easily modified. You will be able to control each LED RGB individually, giving you the ability to create cool lighting effects for your car or perhaps under-cabinet lighting in your kitchen!

LED RGB Strip - Addressable, 5m (APA102)

$ 79.95

Need something a bit longer? These 5-meter-long RGB APA102 strips offer more LEDs, light and options than the 1-meter option. No worries; the length difference won’t affect any functionality.

RGB LED Bar Graph - 48 Segment

$ 29.95

Rounding out the pack today is this 48-Segment LED Bar Graph. This bar graph is perfect for projects requiring display meters with higher accuracy for reading a power charge, volume peak or signal strength. It should be mentioned that this board does not have a very compact footprint, so be sure to prepare to use a bit of space.

That’s it for this week, folks. We hope these new products provide you with plenty of great ideas for new projects. We’ll be back next week with another big post, so be sure to come on back. See you next Friday!

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The GoonieBox challenges guests to solve its riddles

via Arduino Blog

Inspired by The Goonies movie and The Room game, Guido Bonelli has constructed a piece of Arduino-controlled interactive furniture to entertain his guests.

After what appears to be a massive amount of work involving 3D printing, laser cutting, wiring, and programming, Bonelli has come up with a puzzle box that shouldn’t need any explanation. Using button presses and other interactions with it, participants are able to unlock a treasure box in the bottom, a working wooden safe!

Additionally, the box tells time in a very unique way. It has an hourglass that is automatically flipped to indicate minutes, and Roman numerals at the top to reveal hours. You can see how it works and how it was assembled in the videos below!

I wanted to create a unique piece of furniture for my home which my guests could interact with. This time however, I wanted it to be something which I wouldn’t have to explain how it worked. Instead, I wanted mysterious scriptures scribed all over the sculpture to intrigue my guests.

At the heart of GoonieBox is of course an Arduino… Effortlessly whisking away my artistically written 0’s and 1’s into a symphony of movement, sound and game play. Taking approximately 800 hours of build time, GoonieBox is my greatest accomplishment by far in the world of Arduino.

You can find more information on the project’s posting, or check out the author’s interesting Dr.Duino product page.

Sisyphus: the kinetic art table

via Raspberry Pi

Surely if he had been given the opportunity, Sisyphus would have engineered a way out of his eternal punishment of rolling a boulder up a hill. It’s just too bad for him that Raspberry Pi wasn’t around to help. While it’s a far cry from his arduous task, the Pi has been used to power Bruce Shapiro’s Sisyphus, a continuous and ever-changing kinetic art piece that creates unique design patterns in sand using a small metal ball.


Sisyphus is truly mesmerising. We learned this first-hand: at Maker Faire New York earlier this month, it captured the attention of not only the Raspberry Pi crew, but also thousands of attendees throughout the weekend. Sisyphus momentarily drowned out the noise and action of the Faire.

You can think of Sisyphus as a cross between an Etch A Sketch and Spirograph, except this is no toy.

Under the table is a two-motor robot (the “Sisbot”) that moves a magnet which draws a steel ball through the sand. The motors are controlled by a small Raspberry Pi computer which plays a set of path files, much like a music player plays an MP3 file.


Bruce is using Kickstarter in the hope of transitioning Sisyphus from what’s currently a large art installation exhibited around the world into a beautiful piece to be enjoyed in the home, as both furniture and art.

annmarie thomas on Twitter

Sisyphus- Stunning art/furniture kickstarter (fully funded in <a day) by friend Bruce Shapiro.

Bruce says:

Of all works I made, Sisyphus stood out – it was my first CNC machine to break out of the studio/shop. No longer tasked with cutting materials to be used in making sculptures, it was the sculpture itself. It was also unique in another way – I wanted to live with it in my home. I’ve spent the last three years perfecting a home version that’s beautiful, user-friendly, near-silent, and that will run for years.

Like most great Maker Faire projects, it’s centred around a wonderful community. The collaboration and access to tools in Shapiro’s local makerspace helped develop the final design seen today. While Shapiro’s original makerspace has since closed its doors, Shapiro and his fellow members opened up what is now Nordeast Makers. It’s where the production for Sisyphus will take place.


The Kickstarter products come in three styles: an end table, and two different coffee tables. You might want to find another place to display your coffee table books, though, so as to keep Sisyphus’s designs visible…


This Kickstarter won’t be running forever, so be sure to pledge if you love the sound of the Sisyphus.

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