by Connor Archard and Feiran Chen @ cornell.edu:
Our final project was to create a rapid prototyping machine for electrical circuits by repurposing an old pen plotter that we fitted with an electrically conductive pen. Our plotter utilized an atmega 1284P to control the x and y-axis motors, and to raise and lower the pen. We created a web app that allowed a user to draw out circuits quickly, and then send them to be printed out on our plotter over a wifi network as our host computer that maintained the serial connection with the atmega 1284P. The atmega 1284P would receive vectors of x and y coordinates from the host computer that would instruct it on how to move the plotter head. By measuring the position of the plotter head on each axis through the on-chip ADC and two servo potentiometers, we were able move the plotter head to an accuracy of approximately 1/10th of an inch on a typical piece of A4 paper.
Rapid Circuit Prototyping – Circuit Plotting - [Link]
This camera module can perform image processing such as AWB (auto white balance), AE (automatic exposure) and AGC (automatic gain control), for the video signal coming from CMOS sensor. What’s more, in fusion of other advanced technology such as image enhancement processing under low illumination, and image noise intelligent forecast and suppress, this module would output high quality digital video signals by standard CCIR656 interface. OV7670 built-in JPEG decoder supported reatime encoding for collected image, and external controller can easily read the M – JPEG video streams, achieving the camera design of double stream. OV7670 supported motion detection and OSD display function of screen characters and pattern overlay, capable of self-defining detection area and sensitivity.
OV7670 Camera Module DIY Guide - [Link]
by Suzanne Deffree:
The holiday season is in full swing and you may still have a few people to check off your gift-giving list. If you’re at a loss for what to buy the open-source-focused engineer or maker in your life, take a gander at these 8 open-source gifts.
In this list you’ll find out-of-the-box devices, kits, and components for DIY designing, some starting as low as $19.99, with others topping $2100. Be sure to share your own open-source favorites in the comments section and let us know what you think of the ones we’ve included on this list.
8 open-source holiday gifts - [Link]
by w2aew @ youtube.com
The Humanalight is a simple single-cell flashlight kit that will produce usable light, even from a “dead” AA battery. Circuits like these are often called a Joule Thief. This term has been applied to just about any circuit that allows you to boost the voltage from nearly depleted batteries for some other low-power application – such as lighting an LED. Strictly speaking, a Joule Thief circuit is an Armstrong style blocking oscillator that uses a bifilar wound transformer and relies on the saturation characteristics of the core to produce oscillation. This flashlight uses a simple two-transistor relation oscillator. A description of the circuit is given, and its operation is examined by viewing the waveforms on an oscilloscope. The proceeds from the sale of this kit benefit the “Ears To Our World” charity which provides self-powered radios and other technology to rural, impoverished and remote regions of the world.
Circuit Walkthrough: A single cell LED light - [Link]
MUNICH — At Electronica last week, the LED manufacturer Everlight introduced what it claims to be the world’s first colour-temperature tunable LEDs in a simple chip on board (COB) package.
After brightness dimming, tunable color temperature is a feature that allows end users to tune the warmth of the light they receive. Typically, this feature is implemented through the use of multiple LEDs binned from cool white to warm white, behind a diffuser.
With its CHI3030 27V/29W series, Everlight claims to have a very compact solution, with LEDs packaged behind concentric layers of phosphors offering different color temperatures of white. Depending on how much warm white or cool white you choose to light up, you can get a precise color-temperature mix.
New LEDs offer tunable color temperature - [Link]
by Hanne Degans @ phys.org:
At this week’s IEDM 2014, held in San Francisco, California, nanoelectronics research center imec demonstrated an ultra-low power RFID transponder chip. Operating at sub 1V voltage and realized in thin-film transistor technology (TFTs) on plastic film, the chip paves the way for universal sensing applications, such as item level RFID tagging, body area networks (BAN) and environmental monitoring, that require prolonged remote autonomy, and ultimate thinness, flexibility and robustness.
One of the major drivers of the semiconductor industry is the Internet of Things (IoT). Market studies envision a society where billions of autonomous sensor nodes are seamlessly integrated into objects, in the environment and on human bodies, operating independently for months, interacting with each other and connecting to the internet. This IoT is expected to improve and enhance daily-lives through smart houses and smart cars, personal health monitoring and much more.
Ultralow-power RFID transponder chip in thin-film transistor technology on plastic - [Link]
Evaluation samples of STMicroelectronics’ STM32F446 range of MCUs are now available. These devices feature ARM Cortex-M4 based processing units with compact 256 or 512 KB on-chip Flash options and 128KB RAM with built-in memory-extension interfaces, extended connectivity and communication capabilities.
The MCUs use ST’s proprietary ART Accelerator, smart architecture, advanced Flash technology and an embedded ARM Cortex-M4 core to achieve a performance of 225 DMIPS and 608 CoreMark at 180 MHz executing from embedded Flash.
The interface capabilities allow simultaneous communication via multiple interfaces which cater for interactive industrial, scientific, medical, and Internet-of-Things (IoT) applications, while the advanced process technology, together with dynamic voltage scaling, extensive clock gating and flexible sleep modes offer significant power savings.
The STM32F446 from STMicroelectronics - [Link]
A California-based start-up called NanoLambda have developed a low-cost ($10) spectrometer sensor chip called Apollo which makes possible a wide range of new sensing applications. The sensor is capable of measuring individual wavelengths of light and is accurate to 1 nm with 10 nm resolution.
Optical spectroscopy is a very powerful non-invasive diagnostic technique and has been used for decades in many fields including health care. However the equipment cost using traditional methods of spectrum analysis has limited its area of application to professional use only. Using the company’s nano fusion technology NanoLambda have fabricated a sensor from thin nanofilter arrays which reduces the size and cost to about 1 % compared with traditional sensing equipment. The sensor’s sensitivity bandwidth can be defined in the manufacturing process and even allows detection in the infra-red region. The small physical size of the sensor makes it ideal for use for unobtrusive, wearable health monitoring applications.
Spectrometer-on-a-Chip - [Link]
by Michael Mayes @ edn.com:
Although temperature is a fundamental aspect of our lives, it is difficult to measure accurately. Before the era of modern electronics, Galileo invented a rudimentary thermometer capable of detecting temperature changes. Two hundred years later, Seebeck discovered the thermocouple, a device capable of generating a voltage as a function of temperature gradients in dissimilar metals. Today, thermocouples as well as temperature dependent resistance elements (RTDs and thermistors) and semiconductor elements (diodes) are commonly used to electrically measure temperature. While methods for extracting temperature from these elements are well known, accurately measuring temperatures to better than 0.5ºC or 0.1ºC accuracy is challenging (see Figure 1).
Temperature-to-Bits converter helps solve challenges in sensor measurement - [Link]
Lattice Semiconductor has developed two power-saving IP cores intended for use in smartphones and mobile devices. Known as ‘Voice Solution’ the two IPs are: Voice Command supporting hands-free and always-on applications, and Voice Recognition which improves the user experience by enhancing security and reducing false trigger inputs. They essentially act as a processing front-end, allowing the main processor to remain in low power dormant mode until voice commands have been processed and recognized by the Lattice Voice Processor.
Lattice FPGA Voice Processors - [Link]