This week was all about sensors, with the Sensors Converge 2022 show now ramped back up to its full might.
In this article, we round up some of the recent sensor innovations centered around inductive, passive, and resistive sensors for automotive, industrial, IoT, and consumer applications.
Position Sensor Family Adds ISO 26262-Compliant Solution
Automotive system developers are rethinking motor control. With that in mind, Microchip Technology has unveiled a new addition to its portfolio of inductive position sensors, a new IC sensor that will be purpose-built for EV motor control applications.
Microchip hopes its new inductive sensor will feed the EV market’s need for cost-effective and accurate solutions for safety-critical position monitoring. Image used courtesy of Microchip Technology
Hall effect position sensors and magnetic resolver solutions are considered outdated in motor control systems, says the company. Developers are moving towards inductive alternatives to eliminate large magnets and bulky transformer-based designs to enable simpler and smaller PCBs.
Microchip’s LX34070 handles fast sampling rates and it complies with automotive safety integrity level C (ASIL-C). The company claims that it does all that while mitigating an automobile’s DC motors, high currents, and solenoid noise.
LX34070 Advantages Versus Resolvers and Transducers
The LX34070 inductive position sensor provides advantages over magnetic resolvers and linear transducers in cost, size, and reliability. Microchip says the architecture of the LX34070 leverages PCB traces instead of magnetic, transformer-based windings and coil structures, which also cuts down on the total weight.
Since introducing its first high-volume inductive sensor 10 years ago, Microchip says it has worked on PCB-based inductive position sensors in order to avoid bulky magnetic solutions. The sensor works with a primary coil that generates an AC magnetic field that is linked to two secondary coils. Once a smaller metal target disrupts the field, each of the secondary cools receives a different voltage.
This change is captured as a ratio and is used to find the absolute position. The LX34070 implements the same technology at a fraction of the size with a simplified layout for easier integration into EV motor controls, says the company.
New Sensors and Signal Conditioning ICs for the IoT
Recently, Renesas added new sensors and signal conditioning ICs to its family of relative humidity/temperature sensors.
Humidity sensors offer systems to measure and report the moisture and air temperature of the surrounding environment. According to Renesas, market demands for humidity sensors call for accuracy of ±2%, The devices in the Renesas HS sensor family beat that at ±1.5%.
The HS4XXX portfolio relies on low-power consumption and can withstand harsh weather conditions in a small silicon carbide structure, says the company. These relative humidity sensors provide both digital and analog outputs with 1.8 V to 5.5 V voltage. Each member of the HS4 sensor portfolio has both humidity and temperature sensor functionality. The HS4 sensors provide temperature sensor accuracy of ±0.2°C typical.
The ZSSC3281 is Renesas’ latest signal conditioning sensor (SSC) that is able to provide amplification, digitization, and signal correction. The SSC is a dual path sensor and can work on calibrated, continuously operating systems such as HVAC or medical health monitors. With a 32-bit Arm core, this SSC can sense offsets in sensitivity, temperature drift, and non-linearity. More details are available from the ZSSC3281 datasheet.
With the Quick-Connect IoT systems, humidity, temperature, and signal conditioning sensors can be integrated without writing and testing hundreds of lines of code. Image used courtesy of Renesas Electronics
To ease sensor integration for IoT, Renesas provides its Quick-Connect IoT system. The system consists of standardized boards and interfaces. These make it easy for IoT system designers to link a wide range of sensors to MCU/MPU development boards. Rather than writing and testing hundreds of lines of driver code, IoT designers just need to select their sensor from a GUI and write a few lines of code.
Battery-free RFID Sensor is Based on Passive Asygn IC
RFID tags represent a relatively mature technology. But the new twist on RFID tags is to empower them with sensor functionalities. Along just those lines, Tageos has unveiled its EOS-840 Sensor products, a line of battery-free, passive RAIN RFID sensors.
The standard RFID sensor is associated with inventory tracking, retail, and kiosks such as badge or card readers. According to the company, its latest sensors will go beyond the typical usage and be able to detect changes in temperature, strain, and ambient light. Adding these features is expected to enable Tageos to reach industrial applications beyond the current RFID market.
EOS-840 sensors provide a low carbon footprint and are equipped with recyclable inlays and tags. Image (screenshot) used courtesy of Tageos
Tageos’ EOS-840 sensors leverage Asygn’s AS321X IC coupled with an antenna structure to enable firmware updates from on-chip calibration. Asygn is known for designing ICs for high-speed RF, automotive radar architectures, gyros, AI, and RFID sensors. The AS321X is a passive UHF RFID chip with an embedded analog sensor interface and internal sensors. Capturing changes in real-time environmental settings from temperature and humidity to a civil structure’s strain and vibrations.
There are three EOS sensors, each will focus on monitoring a single unit through the integrated AS321X to obtain the highest level of accuracy, providing the user with predictive maintenance capabilities, says Tageos.
The EOS-840 family includes:
- EOS-840T: Detects changes in temperature
- EOS-840LT: Senses changes in ambient light and temperature
- EOS-840ST: Monitors mechanical strain and temperature
Each EOS sensor implements RAIN RFID inlays that have a reading range of up to 30 feet and are battery-free, providing flexibility with systems monitoring in inclement environmental conditions.
A Multi-function Trend in Sensors
Thanks to the magic of semiconductor integration, the trend toward highly-integrated solutions are impacting every type of IC. As you’ve seen in this article, in the sensor arena, this means humidity and temperature sensor functionality sharing the same device, and RFID tags adding multiple types of sensing capabilities. At Sensors Converge 2022 this week, the All About Circuits team saw this trend playing out across the board.
Interested in recent sensor innovations? Read about on in the articles down below.