by Steve Taranovich @ edn.com:
Gas sensing techniques are continually being investigated to improve selectivity and sensitivity of identifying different types of gases. There are resistive gas sensors, quartz crystal microbalance, direct thermoelectric, electrochemical cell and other exotic types such as MEMS-tunable Fabry-Perot filter spectral sensors with lead-selenide detector and pulsed broadband infrared emitter light source. The ams sensor is a resistive type.
The resistive sensor design relies upon heating circuitry for temperature control of the entire system. There are different types of resistive gas sensor techniques and construction. Some are based upon metal-oxide (MOX) thin films which are small in size, low-cost, and low power as well as able to use low-power integrated analog front ends.
ams develops MEMS VOC gas sensor - [Link]
by Mahesh Venkitachalam:
I was in Bhutan last December, and as we travelled to different locations, I kept wondering what the temperature and altitude was, and wished I had some gizmo that would show me these values. Back home, I did a bit of research on altitude sensors, and one that came up was the cheap BMP180 sensor. It measures temperature and pressure, and the latter can be used to calculate the altitude. It’s been lying around with me the past few months, and now I’ve finally gotten around to building a display around it.
Temperature / Altitude / Pressure Display using BMP180 - [Link]
TCS3490 intelligent color sensor’s accurate measurement of color temperature and ambient light intensity enables sophisticated display color management control for smartphones, tablets, notebooks and digital still cameras
ams AG released the TCS3490, a color sensor for portable devices which is ideally suited for light source detection when operating under a wide range of light sources.
Providing accurate color and light intensity measurements, the TCS3490 enables designers of portable devices such as smartphones and tablets to implement more sophisticated display management and brightness control.
This integrated five-channel color sensor has extremely accurate measurements of the Correlated Color Temperature (CCT) of light. As sensors continue to proliferate in today’s mobile electronics market, manufacturers of mobile devices such as smartphones, tablets and laptops can use these measurements to dynamically adapt the display’s color palette to provide the user with a superior viewing experience.
AMS color sensor for mobile devices improves accuracy and offers new light source detection capability - [Link]
Motion sensing is the detection of the change in position of an object relative to its surroundings or vice versa. There are many kinds of motion detector methods: infrared, optics, radio frequency, sound, vibration, and magnetism. These methods differ from each other because each of them uses a different medium and detects different subject (e.g. sound: in Doppler effect, motion is detected by the change in reflected frequency).This project uses PIR (passive infrared) sensor to detect the change in radiation, this can be use on lighting control, temperature control, and motion detection since all objects with temperature above absolute zero emits heat energy in the form of radiation. The term passive refers to the fact that PIR devices do not generate or radiate any energy for detection purposes. It works entirely by detecting the energy given off by other objects.The D204B PIR sensor is used in this project, it contains a material that generates energy when exposed to heat/radiation. The MCP6H94 quad op-amp is used in two stages; amplifier and comparator. The weak signal from the PIR sensor will be amplified by the first two op-amp configured as amplifiers, the amplified signal is then fed to the last two op-amp configured as comparator. The BC548 NPN transistor acting as the switch will be triggered when the comparator’s output gets HIGH, further, switching the transistor will also trigger the relay that is connected to the load (light and/or alarm).
PIR Motion Sensor - [Link]
While trying to create a circuit that detects whether water is flowing through a pipe by measuring the vibration with a piezoelectric sensor, just to see what happens I taped the sensor around my finger and – to my surprise – got values that were a very noise-free representation of my heart rate!
Measuring Heart Rate With A Piezo - [Link]
Infineon Technologies has launched an ultra-high ±5 cm resolution, miniature MEMS (Micro Electro Mechanical Systems) pressure sensor for use in mobile and wearable gadgets and IoT (Internet of Things) devices. The DPS310 is a low-power digital barometric pressure sensor that enables the development of new and enhanced navigation, location, well-being, gesture recognition and weather monitoring applications.
Delivering accurate and stable performance across a wide temperature range, the DPS310 is ideal for indoor navigation and assisted location applications – such as floor detection in shopping malls and parking garages – and outdoor navigation where it can help to improve navigation accuracy or support ‘dead reckoning’ when GPS signal is not available. In addition, the ability to provide accurate data for calculating elevation gain and vertical speed suits activity tracking in mobile and wearable health and sports gadgets, while ultra-precise pressure measurement opens up new possibilities for gesture recognition and the detection of rapid weather changes.
Low-Power Barometric Pressure Sensor from Infineon Delivers New Levels of Accuracy - [Link]
At the 2015 Mobile World Congress in Barcelona, Spain, the leading sensor manufacturer Sensirion will present a new multi-pixel gas sensor, plus a new barometric pressure sensor. Both new sensors, which rank among the smallest yet most accurate in their class worldwide, are capable of measuring indoor air quality (IAQ), the gases in a person’s breath, and barometric air pressure, as required for indoor navigation applications. The new sensors complement Sensirion’s existing product offering for wearables, smartphones, tablets, and the Internet of Things (IoT), and confirm the company’s status as the only sensor manufacturer to offer a complete solution all the way from sensor to cloud. With its trusted humidity and temperature sensors already established on the market, Sensirion is now expanding its range of environmental sensors to include gas and pressure sensors.
Sensirion presents the smallest and most accurate Gas and Pressure Sensors – [Link]
by Susan Nordyk @ edn.com:
The latest addition to STMicroelectronics’ portfolio of environmental sensors, the UVIS25 provides a direct digital output of UVI (ultraviolet index)—the international measurement of the strength of ultraviolet radiation, primarily from the sun, at a given place and time. Aimed at wearable devices, smart-phone, and tablet applications, the UVIS25 is sensitive to UV waves in the 200-nm to 400-nm range. This range covers the UV-A (315-nm to 400-nm) and UV-B (280-nm to 315-nm) wavelengths, which are of greatest concern to human health.
The device furnishes more than just sensing, calculating the UVI internally and eliminating the need for external processing algorithms or calibration on the customer’s manufacturing line. Key specifications include a UVI output range of 0 to 15 with a resolution of just 1/16, SPI and I2C interfaces, a supply voltage range of 1.7 V to 3.6 V, and the ability to provide updated UVI values as often as every second.
UVIS25 – Wearable sensor measures UV index - [Link]
by Francesco Truzzi :
Some time ago I came across a new chip from TI, the HDC1000. It’s a temperature and humidity sensor with I2C interface and requires little to no additional components. It comes in an 8BGA package: we can all agree it’s pretty small.
Some of the peculiar characteristics of this chip are that it has a DRDYn pin which goes low any time there is a new reading from the chip (so you can precisely time your requests) and that the sensor is located on the bottom of the IC, so that it’s not exposed to dust and other agents that may false the readings. Also, it has an integrated heater that can remove humidity from the sensor.
So I developed a very small breakout board for this chip as well as an Arduino library (yay, my first one! raspberryPi and nodemcu might come next).
HDC1000 temperature and humidity sensor breakout, with Arduino library! - [Link]
The VL6180X is the latest product based on ST’s patented FlightSenseTMtechnology. This is a ground-breaking technology allowing absolute distance to be measured independent of target reflectance. Instead of estimating the distance by measuring the amount of light reflected back from the object (which is significantly influenced by color and surface), the VL6180X precisely measures the time the light takes to travel to the nearest object and reflect back to the sensor (Time-of-Flight).
Combining an IR emitter, a range sensor and an ambient light sensor in a three-in-one ready-to-use reflowable package, the VL6180X is easy to integrate and saves the end-product maker long and costly optical and mechanical design optimizations.
VL6180X – Proximity sensor, gesture and ambient light sensing (ALS) module - [Link]