Scientists at Tufts University in Massachusetts have announced the development of implantable circuits which are capable of being dissolved and absorbed into the human body over time. Known as resorbable or transient electronics these ultra micro devices are covered by magnesium oxide, along with an outer jacket of silk allowing them to be implanted into the human body where they would remain functional for a period of time before dissolving and being absorbed into the body.
Obvious potential uses are in medical research and diagnostic testing. However, given the project’s DARPA funding, there would appear to be a number of intelligence related uses contemplated.
We are developing an acrylic board witch will have a Bus Pirate and a small breadboard attached to it. This will be a part of a kit we are thinking about.
Connecting your Arduino to the internet is cool, but it’s even cooler to connect over WiFi. Luca explains how to connect your Arduino Ethernet shield to a cheap WiFi router to give it WiFi access. If you want to boost the security and privacy of your home’s wifi network, you may buy residential proxies.
Sometimes however it could be easier (and maybe cheaper!) to connect an Arduino to the Wi-fi network using your ethernet shield in conjunction with a wireless router.
I found the TL-WR702Nnano router by TP-LINK that, with a cost of about 20€ on eBay, can work also as a wireless client: in this mode the router acts like a “bridge” between the device connected to its ethernet port and a Wi-fi network.
Last week we met with Dimitri, designer of the Smartduino, in Shenzhen, China. Dimitri is a 6 year veteran of the Huaqiangbei electronics wholesale market. He first arrived 6 years ago, and quickly opened his own stand because it seemed like the best way to make deals in the market is to become part of it. He now runs 8 stands all around the market and says each building has a unique story to tell.
Dimitri started with a single stand in on the third floor of a building, the top floor at the time. That building now has 10 floors, and another building is being built next to it. The pace at which the Huaqiangbei market is developing is staggering. In his estimate the market has grown a 100 times in the last 6 years.
View of Shenzhen from Dimitri’s office.
Dimitri’s attraction to Shenzhen is based on getting things done. Only in Shenzhen can you think up an idea on Monday, and have a working prototype in your hands on Thursday. Proximity to the world’s largest wholesale electronics market means that any IC, any connector or part you need, is but a few blocks away. It’s like having your local electronics shop be as stocked as Mouser or DigiKey, without the inflated retail prices.
It’s not just electronic parts, but anything required for the full project is available. Solder paste stencils are delivered the next day, PCBs are at your doorstep in 48 hours, and all the tools you might are just steps away.
As the market grows and becomes more of a tourist spot, Dimitri thinks prices are getting higher. Like many people we talked to Shenzhen, he is utilizing more and more online part sources. Chinese sites let buyers post requests, and the sellers contact them directly with offers. Dimitri now conducts 80% of his sourcing in this manner.
Dimitri does his prototyping in house. He has a solder paste stencil rig, and a reflow oven capable of cooking 9 Arduino sized boards in 6-7 minutes. He feels this is much faster than hand soldering, and quick-turn stencils make it super convenient.
The successfully kickstarted Smartduino* is a snap-together prototyping platform based on the Arduino and a “Smart Bus” connection between board. A core board with an Arduino-compatible AVR microcontroller is broken out into the Smart Bus that can be connected to over 50 different extension boards simultaneously. The project is aimed at people who find the full Arduino platform too cumbersome for a small commercial product, but don’t want to design custom boards.
A huge thanks to Dimitri for a tour of his office, high up overlooking Huaqiangbei.
*While we were in China this project became the subject of controversy. We present this interview as a documentary of our meeting with Dimitri who is very passionate about his projects.
Yesterday Ian talked with Chris and Dave on The Amp Hour podcast. Hear about how Dangerous Prototypes got started in the open source hardware, the Bus Pirate, and Sick of Beige cases and standard PCBs. We also discuss how our fulfillment with Seeed Studio functions, and the process of developing a project from idea to production. Open 7400 competition was mentioned, as well as the idea of hosting an open lab tool contest next year.
Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters.
Don’t forget there’s free PCBs three times a every week:
Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch it every Sunday, right here on the blog
Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
Facebook PCB Friday. Free PCBs will be your friend for the weekend
We’ll contact you via Twitter 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.
As a final project in their class Mohamed and Michael developed the Virtual Archery game. It’s based on the ATmega1268p, an accelerometer, and a stretch sensor. The stretch sensor lets the game know how much force there is behind the arrow, while the accelerometer records it’s exiting direction. Using these two parameters the game extrapolates where the arrow will land in relation to the target.
The ATmega1284P microcontroller uses its internal analog-to-digital converter (ADC) to determine when the stretch sensor has been drawn and released, communicates with an external ADC over SPI to obtain the orientation of the bow from an accelerometer, and displays the expected location of an arrow fired by the user. Another arrow is readied by the push of a button on the bow. When the bow is fully drawn, LEDs will light up simulating the arrow. The lights are turned off when the arrow is released.
Beginners to the MCU scene may want to check out the Arduino Esplora. This new board design is open source and based on the Arduino Leonardo. The Leonardo’s ATmega32u4 is augmented by the inclusion of a number of on-board peripherals, including a microphone, LDR, accelerometer, potentiometer, analog joystick, temperature sensor and sound and light output interfaces. The design is rounded out by two Tinkerkit input and output connectors along with a socket for a color TFT LCD screen.
The board is designed to be simple to use, and detailed instructions are available to help newcomers to MCUs and the Arduino platform learn and develop programming skills without the need to solder or find and install compatible peripherals. All this comes at a list price of $58 for the Esplora, which will initially be sold only through Radio Shack. (We could find no listing on their website.)
We’re editing the tomorrows video. It’s the interview with Dimitri from the recently controversial Smartduino project, a market veteran with 7 years experience running market stalls and exporting components.
We’re working on a Bus Pirate kit, and today we designed an acrylic board which will hold the Bus Pirate and a half-sized breakout board.
We converted the original 6.xx Eagle version of the header-less connector to a 5.xx version. We really liked this design, and are seriously thinking of incorporating it in our future projects.
One of the most common techniques in DIY PCB etching is the toner transfer method. Tom added a twist to the standard method by adding the use of a stovetop in the toner transfer process. He wrote a tutorial describing in depth how you could recreate his results.
I have been trying out a new technique for toner transfer. Heat a cast iron hotplate on the stovetop to 175oC, as measured on a thermocouple, then turn the heat right down. Put a sheet of paper on the hotplate followed by the copper clad board, image side down. Then apply pressure with a rolling pin for 2-5 minutes. It might work for double sided, too.
These modules are designed to connect to a booster pack i have yet to design for a Stellaris Launchpad ( overkill? perhaps..) via the FFC on the left side of the board. The motor would be powered by 12V from a computer PSU via the screw terminals on the bottom. I tried to stay away from .1″ pins for the most part. I took inspiration from bearmos’ cnc controller with the thermal vias.
If you build a free PCB we’ll send you another one! Blog about it, post a picture on Flicker, whatever – we’ll send you a coupon code for the free PCB drawer.
Sebastian has been tinkering with the Analog Devices ADF4351 eval board and written a review. “The ADF4351 from Analog Devices (ADI) is a modern wideband PLL synthesizer with integrated low phase noise VCO. It is capable of generating signals between 35 MHz to 4400 MHz with a very low jitter of typical 0.3 ps. ADI agreed to send me the EVAL-ADF4351EB1Z, an evaluation board for the ADF4351, for review purposes.” Being an amateur radio operator (KF5OBS), Sebastian is already thinking about possible applications for this chip as a modern alternative to synthesizer chips used in some earlier radio designs. His complete review can be found on Sebastian’s Jaunty Electronics website.
According to the ADI website this eval board lists for $175, though Sebastian reports that the chip itself goes for $8.25 each (when purchased in bulk.)
Here’s a tutorial from Maxim describing the thermal specifications in IC packages. All the devices used in a project dissipate heat, and if not properly cooled they will fail. This article will bring you closer to understanding the thermal specs quoted in datasheets.
Thermal characterization of packages is critical for the performance and reliability of IC applications. This article describes the standard thermal package properties: thermal resistance (known as “theta” or Θ), ΘJA, ΘJC, and ΘCA. Thermal calculations and references for more information on thermal management are provided.
We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service.
This week two random commenters will get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB.
You get unlimited free PCBs now – finish one and we’ll send you another!
Don’t forget there’s free PCBs three times every week:
Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
Facebook PCB Friday. Free PCBs while you wait for the weekend
Ever wonder what’s happening on your vehicle’s data bus? Here’s an open source software tool suite which hopes to open this data to your Linux box. “Freediag is a suite of vehicle diagnostic protocols and an OBD II (mostly) compliant scanning tool, currently for Linux platforms. Multiple graphical user interfaces for the scan tool are under development – but right now, you have to use a command-line interface to scantool.
OBD II is a standard for vehicle diagnostics relating to emissions implemented on all US vehicles since the mid 1990s. Europe has just introduced a standard called EOBD which is basically the same.”
You can find the code on Sourceforge. For details on using the program, as well as supported vehicle interfaces, see the program documentation.
This is a program which seen sporadic development over the years, with the last code release in 2011. They welcome any assistance in code dev and testing.
Here’s a video from Linear Technology describing how to drive capacitive loads fast. The proposed solutions is to use multiple op-amps in a parallel configuration to achieve the high-speed requirements.
Certain video and other technologies require driving planar conductive surfaces fast. Unfortunately, the surfaces can have high capacitance, which means that driving them fast takes high currents. This complicates the amplifier design but the situation extends beyond just the amplifier. Between the amplifier and the capacitive load, there is necessarily some length of transmission line.
Analog Devices describes why it’s a bad idea to drive capacitive loads with op amps. If you’re forced to drive a capacitive load, this video also provides a possible solution to the stability issues.
At last summer’s DEFCON 20 conference, speakers FX and Greg gave this presentation on exploring Huawei routers. These devices are growing in market share in many countries, even used by tier one ISPs. They explore the device’s software platform and security, highlighting the architecture, configurations and services available
as well as summarizing their efforts in reversing the router’s OS.
