By Stephen Evanczuk:
Sensor data acquisition underlies many deeply embedded applications and plays a central role in the evolving Internet of Things (IoT). With the trend toward reliance on energy harvesting for power, sensor-based designs require increasingly effective solutions for processing sensor signals efficiently and accurately. Among available alternatives, specialized sensor-signal conditioning ICs such as those from Analog Devices, Maxim Integrated, and Texas Instruments offer a drop-in solution for sensor-signal acquisition.
Sensors typically produce small signals that require amplification to boost the dynamic range of the signals, as well as compensation to correct for offset, temperature, and non-linearity response of the sensors themselves (Figure 1). To meet these challenges, designers can turn to a variety of digital and analog methods.
Signal Conditioners Offer Drop-in Sensor Solutions for Energy-Harvesting Designs - [Link]
Bluetooth® Low Energy (BLE) may not be part of your electronic designs just yet, but chances are it will be soon. This wireless connectivity technology has experienced explosive growth over the last three years. It now provides low-power connectivity to millions of electronic devices, such as smart watches, fitness trackers, smartphone accessories, and medical monitors. Thanks to upcoming technical enhancements, BLE is poised to become even more pervasive in the next generation of consumer electronics and the emerging Internet of Things.
Many of the enhancements have been incorporated in Bluetooth 4.1, a recent update to the core specification. Among them are support for more efficient bulk data transfers, greater flexibility in communications between devices, simultaneous dual-mode roles, and the first steps toward IP-based communications. Taken together, these technical improvements make BLE even more attractive from power consumption, performance, and cost standpoints.
In addition to the enhancements outlined in Bluetooth 4.1, the BLE chips themselves have been continuously improving. Thanks to efficiency improvements, transmission power consumption in the second generation of BLE will fall by about 66 percent with no loss of range or performance.
Moving Forward With Bluetooth Low Energy - [Link]
Hemal Chevli wrote an article detailing his new tool the GLCDTerm that reads serial data without PC on GLCD:
I’m calling it GLCDTerm(spin-off from GTKTerm), this handy tool reads TTL serial data and displays it on GLCD. This is the first time I’ve used a GLCD in any of my projects. It runs on m328 using arduino bootloaer and the awesome GLCD library. I first made a prototype on one of my arduino clones, Below is the video running diagnostics program.
Read serial data without PC on GLCD – [Link]
by University of Twente:
Researchers from the University of Twente MESA+ research institute, together with the company SolMateS, have developed a new type of transistor to reduce the power consumption of microchips. The basic element of modern electronics, namely the transistor, suffers from significant current leakage. By enveloping a transistor with a shell of piezoelectric material, which distorts when voltage is applied, researchers were able to reduce this leakage by a factor of five (compared to a transistor without this material). An article presenting the prototype of the transistor appears in the June issue of IEEE Transactions on Electron Devices, an authoritative scientific journal in the field of transistor research.
Prototype of new transistor for lower power consumption - [Link]
In this episode Shahriar explores the world of filters! Starting from a simple lumped RC filter, he briefly covers the theory before moving onto measurement techniques. The bandwidth of the filter is verified experimentally in the time domain. A more complex RLC band-stop filter is also demonstrated with a tune-able inductor which is measured using an RLC meter. Using a Rigol spectrum analyzer with built in tracking generator and an active probe, the frequency response of the filter is measured. Several other packaged filters are also demonstrated and a microwave band-pass filter is disassembled to reveal its internal construction.
Tutorial on Passive Filters, Data Transmission and Equalization - [Link]
Dave explains, shows, and measures a potentially big trap with using high value ceramic capacitors. Is your 10uF capacitor really 10uF in your circuit? You might be shocked! Those humble X7R caps you think are a “stable” dielectric? think again… Class II and above ceramic capacitors can vary their capacitance drastically with DC bias voltage level and also the applied AC voltage.
EEVblog #626 – Ceramic Capacitor Voltage Dependency - [Link]
Due to some intermittent voltage drop issues on the first revision of PowerShield I refactored the design and released a new PowerShield R2 based on the LTC3525 fixed 5V booster that should address this issue. This is a much more expensive chip than the TPS61220, others have used the Linear Technology boosters with success so hopefully it’s more reliable, but price will reflect this. It also means there is no switching between 3.3V and 5V output any more. For 3.3V projects, a Lipo can be connected directly to Moteino and the onboard regulator will provide up to 250mA of current to the Moteino itself and any other peripherals attached.
PowerShield R2 released - [Link]
Blend Micro is an Arduino development board with built-in Bluetooth 4.0 Low Energy (aka BLE or Bluetooth Smart) connectivity targeted at developers using the Arduino platform to design IoT applications. The board uses an Atmel ATmega32u4 micro-controller and the Nordic nRF8001 BLE chip.
The Blend Micro runs in the BLE peripheral role only, allowing BLE central role devices to establish communication.
Blend Bluetooth with an Arduino Platform - [Link]
One basic need of a computer scientist is to measure the power that a USB device drains off the PC. This device is plugged between the PC and a USB device and displays the current on an LCD. For currents under 100mA it is displayd in 0.5mA steps and 1mA steps for currents over 99.5mA. It is built with an AVR programmed in assembler.
USB Power Monitor - [Link]