Melexis launches ultra-high precision pressure sensor chip for automotive applications

November 18, 2022, Tessenderlo, Belgium - Melexis, a global microelectronics engineering company, announces the launch of a new series of PCB-free pressure sensor chips. The chips in this series can maintain ultra-high accuracy throughout their entire service life. With this outstanding performance, the last generation of internal combustion engine (ICE) vehicles will become more environmentally friendly in all circumstances.

Pressure sensor application promotional image

Melexis, a global microelectronics engineering company, has launched a new series of integrated pressure sensor chips. This series of products is designed for automotive engine management. The MLX90824 measures absolute pressure and provides a digital output signal of the SENT protocol, while the MLX90822 provides an analog voltage output signal. These devices are factory calibrated and can measure full-scale pressures in the range of 1 bar to 4 bar.

Laurent Otte, Senior Product Line Manager at Melexis, explains why this product range helps customers: “The sensor chip in this range maintains an accuracy of +/-0.5% FS (Full Scale) over its entire service life. Thanks to the PCB-free package, the measurement accuracy is not affected by the integration of the sensor chip”. Extremely precise and stable pressure measurement helps optimize engine management to ensure fuel savings and reduced emissions.

The MLX90824 and MLX90822 integrate sensors, signal processing circuits, SENT or analog output drivers, and all basic passive components. The MLX90824 (SENT output) provides a pre-calibrated negative temperature coefficient (NTC) thermistor input. Customers do not need to perform terminal calibration when connecting the NTC through the pressure sensor chip. Excellent overvoltage (+40 V) and reverse voltage (-40 V) protection mechanisms are integrated into the chip. With this wide protection range, trucks will be more energy-efficient and environmentally friendly. The operating temperature range of this series of pressure sensors is -40 ℃ to 160 ℃, and can even withstand temperatures up to 170 ℃ for a short time, supporting the trend of engine miniaturization.

MLX90822 Product Image

The MEMS sensing element of the MLX90824 and MLX90822 consists of a micromechanical sensing membrane. The sensing membrane is bonded around a cavity etched in the silicon substrate. A reference vacuum is formed in the cavity. If the absolute pressure of the environment changes, the sensing membrane reacts. The piezoresistive elements implanted in the sensing membrane are connected to form a Wheatstone bridge to generate a signal. The onboard front-end electronics then amplify the signal and convert it into a digital signal. The 16-bit digital signal processing (DSP) is responsible for temperature compensation. Finally, the result is provided via the SENT output or analog output.

Both the MLX90824 and MLX90822 have been developed as Safety Element Out of Container (SEooC) in compliance with ISO 26262. The MLX90824 is ASIL B compliant and the MLX90822 is ASIL A compliant.

MLX90824_Product Image

“By acquiring stable and accurate pressure and temperature data, the engine can be managed optimally over the entire service life of the vehicle. This has a positive impact on fuel savings and emissions reduction,” said Karel Claesen, Product Manager for Pressure Sensors. “The MLX90824 and MLX90822 are optimized for the latest engine designs and new operating conditions.”

Last but not least, for motorcycles and other equipment with small engines, such as chain saws, lawn mowers, etc., the sensors must have very fast refresh rates and step responses. The MLX90822 output step response is 3 times faster than other pressure sensors previously launched by Melexis, which is enough to meet this requirement.

The MLX90824 and MLX90822 help OEMs continue to reduce emissions and combat rising fuel prices by lowering fuel consumption. The chips ensure that cars, trucks and motorcycles meet the latest stringent emissions standards.

For more information, visit www.melexis.com/MLX90824 and www.melexis.com/MLX90822 or contact us at sales@melexis.com.