"World's smallest" pyro-electric sensor features digital interface

Measuring just 5.65mm by 3.7mm and with a height of less than 1.55mm, the ezPyro component is a multi-chip package that incorporates a sensor with an ASIC processing unit, producing four channels of signals from a digital interface.

Pyreos’s pyro-electric sensors allow its devices to have response times measured in milliseconds, instead of a timescale measured in seconds by some rival components.

Current consumption for a single channel is less than 3.5μA, rising to only 72μA in high-power mode, compared with figures measured in mA for similar products.

The sensors can also operate over a wide range of temperatures, from -40C through to 85C, demonstrating the durability of the components.

Andrew Wallace, Chief Executive at Pyreos, which was spun out of Siemens in 2007, commented: “The ezPyro component has the potential to become a real game-changer for our customers. The chip operates in current mode instead of voltage mode and so it is very responsive and has a very broad dynamic range, which means it can sense very small signals and still measure very large signals.”

“The precision of the analogue-to-digital converter (ADC) is 15-23 bits, which gives a very precise read out of information and offers a vast range of operations.  As well as consumer applications, ezPyro will be a useful tool in the industrial market,” he added.

“Our ezPyro uses the inter-integrated circuit (I2C) serial computer bus and so standard microcontrollers can be used with our sensor, removing the need to write special software to control it and reducing cost and timescale of integration.”

Applications for the ezPyro component include:

• detecting motions and gestures using an array of two-by-two detectors, allowing it to capture data not just on movement but also direction of movement;
• flame detection, with the dynamic range allowing for both small and large flames to be detected at a distance, while also reducing the chance of false-positive readings from sources such as direct sunlight or halogen lamps;
• and gas analysis, with the sensor being able to detect the presence and concentration of poisonous gases such as carbon monoxide and methane to improve safety, and the build-up of carbon dioxide or nitrogen oxides for environmental monitoring.