Sensor + Test 2017 Highlights: Mini Pressure Sensors for Wearables and a Magnetless Position Sensor

The sensing revolution is accelerating amid an uptake in automotive, consumer and industrial designs.

Sensors and their measurement and calibration capabilities are in the spotlight at the Sensor + Test show held from May 30th to June 1st this year in Nurnberg, Germany.

Suppliers from across the globe are showcasing sensors, actuators, signal conditioners, calibration devices, etc. for a wide array of applications, including automotive, consumer, and industrial control.

Here is a sneak peek of two sensing solutions displayed on the Sensor + Test show floor.

A Position Sensor Without Magnets

IDT came to the show with its new inductive position sensor for automotive applications. The position sensor IC interfaces with thin PCB-based coils and a metallic target to determine the position and provides accurate position data back to the system.

These contactless position sensors are magnet-free, and that lowers materials costs as no shielding is required. Moreover, it provides immunity from magnetic stray fields, which is a critical requirement in automotive applications because magnetic fields can disrupt other sensors in vehicles.

 

The contactless position sensor is not sensitive to magnetic fields, and that makes it suitable for automotive, consumer, and industrial applications. Image courtesy of IDT.

 

The traditional magnet-based sensing solutions measure angular position using variations of magnetic field amplitude induced by the displacement or rotation of a moving magnet. But these magnet-based sensors are expensive and have operating temperature limitations.

The single-chip design allows these devices to be used as rotary end-of-shaft (on-axis) sensors, rotary side shaft (off-axis) sensors, linear motion sensors, and arc motion sensors. IDT claims that its inductive position sensors are automotive qualified and are compliant to ISO 11452-8, which also makes them suitable for use in industrial and consumer applications.

Miniaturization of Pressure Sensors

Another key highlight from the show: Infineon's DPS310, a miniaturized digital barometric pressure sensor capable of measuring both pressure and temperature. It uses a sealed capacitive sensing element for pressure measurement, and that guarantees high precision and accuracy (± 5 cm), even across temperature changes.

The internal signal processor converts the output from the pressure and temperature sensor elements to 24-bit results. Next, the sensor's FIFO stores the latest 32 measurements, which allows the processor to remain in a sleep mode for a longer period between readouts. This is how FIFO lowers the power consumption.

 

The block diagram of the barometric pressure sensor for mobile and wearable devices. Image courtesy of Infineon.

 

Infineon is targeting this miniaturized pressure sensor for mobile applications and wearable devices. For indoor navigation, it can be used for floor detection in shopping malls and parking garages.

And for outdoor navigation, the sensing device facilitates GPS start-up time and accuracy improvement as well as dead-reckoning in tunnels. Next, in healthcare and sports applications, the DPS310 pressure sensor can provide accurate elevation gain, vertical speed, and calorie consumption.

 

Featured image used courtesy of Sensor + Test 2017.