Davide Gironi writes:
DS18B20 is a programmable resolution 1-wire digital thermometer.
It has an operating temperature range of -55°C to +125°C and is accurate to ±0.5°C over the range of -10°C to +85°C.
This library is an AVR implementation to retrive temperature from DS18B20.
Built using the reference document: “Using DS18B20 digital temperature sensor on AVR microcontrollers” by Gerard Marull Paretas, 2007.
A DS18B20 1-wire digital thermometer AVR ATmega library - [Link]
Cambridge Sensors Ltd have announced the appointment of the ASE group to assemble and test there latest tiny (currently the world’s smallest) gas sensor. The 2.0mm x 3.0mm cavity DFN package developed together with ASE enables the integration of gas sensors into devices such as smartphones, tablets and wearable devices where it has previously not been physically possible.
The CCS800 product family of ultra-low power miniature gas sensors can be used for detecting Ethanol (Alcohol) and hazardous gases such as Carbon Monoxide (CO) and a wide range of Volatile Organic Compounds (VOCs) including Formaldehyde. According to Fuyu Shih the vice president of ASE Europe: “The Global emergence of sophisticated electronics geared towards improving lifestyle and efficiency is fuelling the sensor market, making it one of the fastest growing areas of innovation within the semiconductor industry”.
Smartphone Nose - [Link]
Project is based on Holteks IC HT7610A, which is a CMOS LSI chip designed for use in automatic PIR lamp, flash or buzzer control. It can operate in 3-wire configuration for relay applications. In our project we have used relay instead of Traic to connect any kind of load in output, HT7610B IC is suitable for traic and HT7610A for Relay application. The chip is equipped with operational amplifiers, a comparator, timer, a zero crossing detector, control circuit, a voltage regulator, a system oscillator, and an output timing oscillator.
Its PIR sensor detects infrared power variations induced by the motion of a human body and transforms it to a voltage variation. If the PIR output voltage variation conforms to the criteria (refer to the functional description), the lamp is turned on with an adjustable duration. The circuit doesnt required step down transformer and can work directly by applying 110V AC or 220V AC (Capacitor C7 needs to change for 220V AC (0.33uF/275V) and 110V AC (0.68uF/275V)
PIR Sensor - [Link]
Freescale have introduced a new range of 3-axis accelerometers offering high sensitivity at low power consumption. According to Freescale the FXLN83xxQ family is capable of detecting acceleration information often missed by less accurate sensors commonly used in consumer products such as smartphones and exercise activity monitors. In conjunction with appropriate software algorithms its improved sensitivity allows the new sensor to be used for equipment fault prognostication (for predictive maintenance), condition monitoring and medical tamper detection applications.
High sensitivity Accelerometer Family - [Link]
Learn how to create your own low cost wireless sensors and connect them to the world.
Store your sensor data at home or in our cloud. We provide fancy graphs and other great online tools to help you manage and analyze your sensor data!
mysensors.org – Learn how to create your own low cost wireless sensors - [Link]
Water Level Alarm is a simple project to detect and alarm once the water level in tank or Aquarium reaches at certain level. Circuit is based on popular NPN transistor BC547 which act as switch, Sensor also made on PCB, when the water reaches the sensor PCB, base of transistor connected to positive supply, in consequence transistor act as switch and activate the buzzer.
Water Level Alarm - [Link]
A new type of sensor being developed by a team of researchers at the University of California, Berkeley based on Plasmon laser technology is so sensitive it may be able to detect the presence of land mines in situ. In a paper published recently in the journal ‘Nature Nanotechnology’ a team of researchers led by Xiang Zhang, UC Berkeley professor of mechanical engineering, have outlined how they have been able to find a way to increase the sensitivity of a light-based plasmon sensor to detect minute concentrations of explosives. The new sensor consists of a layer of magnesium fluoride sandwiched between a semiconducting layer of cadmium sulfide, and a sheet of silver.
New Sensor could sniff out Land Mines - [Link]
Miniature calibrated humidity and temperature sensor Sensirion SHTC1 is usable even in space – limited applications.
Really miniature dimensions and a low price are main benefits of new calibrated sensors SHTC1 from production of company Sensirion. If you ever tried well known sensors series SHT2x, probably you´ve been surprised by their small dimensions (3,2×3,2x2mm). However the new sensor SHTC1 shifts dimensions a level further, or better said – lower. The result is a DFN package with dimensions of only 2x2x0.75mm, what in praxis represents a package, which you may not notice at a cursory look at a populated PCB. That´s why the SHTC1 is primarily intended for mobile applications and everywhere, where a spared space and a minimal power consumption are beneficial.
Taking a low price in mind, the guaranteed accuracy of SHTC1 chip is relatively excellent, roughly on a level of SHT21. Typical accuracy of ±3% in a range of 20-80% RH and ±0.3°C is probably fully sufficient for majority of applications. 1.8 V supply voltage and ultra low power consumption below 1uJ/measurement are ideal for battery powered devices. SHTC1 supports I2C fast mode (0-400 kHz). This small package practically can´t be soldered by hand, but it is relatively easily possible by means of a solder paste and a hot-air soldering station.
Also the SHTC1 is produced by a well proven CMOSens technology, which proves its reliability and a long-term stability in industry. Similarly, the SHTC1 also isn´t only a “sensor” but a ready-made calibrated solution containing 2x sensor, low-noise amplifier, A/D interface, data processing unit with calibration data in a ROM and a communication interface. Detailed information can be found in the Sensirion SHTC1 datasheet and the Sensirion Humidity flyer.
We´ve got samples ready for you!
If you´re interested in trying this perspective sensor, take part in a contest below the article, or contact us on a well known address email@example.com.
SHTC1 we keep so far as an item upon order, but we´re able to supply it to you in a short leadtime and soon it will be a standard stock item.
SHTC1 – humidity and temperature from a pin head - [Link]
Ray has a great reverse engineering project! Check out more on his blog rayshobby.net. [via]
At the Maker Faire this year I got lots of questions about soil moisture sensors, which I knew little about. So I started seriously researching the subject. I found a few different soil sensors, learned about their principles, and also learned about how to make my own. In this blog post, I will talk about a cheap wireless soil moisture sensor I found on Amazon.com for about $10, and how to use an Arduino or Raspberry Pi to decode the signal from the sensor, so you can use it directly in your own garden projects.
What is this?
A soil moisture sensor (or meter) measures the water content in soil. With it, you can easily tell when the soil needs more water or when it’s over-watered. The simplest soil sensor doesn’t even need battery. For example, this Rapitest Soil Meter, which I bought a few years ago, consists of simply a probe and a volt meter panel. The way it works is by using the Galvanic cell principle — essentially how a lemon battery or potato battery works. The probe is made of two electrodes of different metals. In the left picture below, the tip (dark silver color) is made of one type of metal (likely zinc), and the rest of the probe is made of another type of metal (likely copper, steel, or aluminum). When the probe is inserted into soil, it generates a small amount of voltage (typically a few hundred milli-volts to a couple of volts). The more water in the soil, the higher the generated voltage. This meter is pretty easy to use manually; but to automate the reading you need a microcontroller to read the value.
Reverse engineer a cheap wireless soil moisture sensor using Arduino or Raspberry Pi - [Link]