Melexis announced the launch of a new series of PCB free pressure sensor chips. This series of chips can maintain ultra-high accuracy throughout its service life. With this excellent performance, the last generation of internal combustion engine (ICE) cars will become more environmentally friendly in any case. This series of products is specially designed for automobile engine management. MLX90824 measures the absolute pressure, provides SENT protocol digital output signal, and MLX90822 provides analog voltage output signal. These devices are factory calibrated and can measure the pressure in the full range of 1 bar to 4 bar.
Package Diagram
Laurent Otte, senior product line manager of Melexis, explained the reason why this series of products can help customers: "This series of sensor chips can always maintain an accuracy of+/- 0.5% FS (full scale) throughout the service life of the sensor chips. Because of the use of PCB free packaging, the measurement accuracy is not affected by the sensor chip integration". Extremely accurate and stable pressure measurements help optimize engine management to ensure fuel savings and reduce emissions.
Absolute Maximum Ratings
The MLX90824 and MLX90822 integrate sensors, signal processing circuits, SENT or analog output drivers, and all basic passive components. MLX90824 (SENT output) provides a pre calibrated negative temperature coefficient (NTC) thermistor input. When the customer connects NTC through the pressure sensor chip, terminal calibration is not required. The chip integrates excellent overvoltage (+40V) and reverse voltage (- 40V) protection mechanisms. With this wide range of protection, trucks will be more energy-saving and environmentally friendly. The operating temperature range of this series of pressure sensors is - 40 ℃ to 160 ℃, and even can withstand a temperature of up to 170 ℃ for a short time, supporting the trend of miniaturization of the engine structure.
Pin Definitions and Descriptions
The sensing element MEMS of MLX90824 and MLX90822 includes a micromechanical sensing film. The sensing film is bonded around the cavity etched on the silicon substrate. A reference vacuum is formed in the cavity. If the absolute pressure of the environment changes, the sensing membrane will react. The piezoresistive elements embedded in the sensing film can be connected to form a Wheatstone bridge to generate signals. Then, the front-end electronic components onboard will amplify the signal and convert it into a digital signal. 16 bit digital signal processing (DSP) is responsible for temperature compensation. Finally, the results are provided via SENT output or analog output.
Absolute Pressure Sensor with SENT output Datasheet
Both MLX90824 and MLX90822 are developed as independent security units (SEooC) and conform to ISO26262 standard. MLX90824 can meet ASIL Level B requirements, and MLX90822 can meet ASIL Level A requirements. "By obtaining stable and accurate pressure and temperature data, the engine can be optimally managed for a long time throughout the service life of the vehicle. This has a positive impact on fuel saving and emission reduction." "The MLX90824 and MLX90822 have been optimized based on the latest engine design and new operating conditions," said Karel Claesen, Product Manager, Pressure Sensors
Last but not least, for motorcycles and other equipment using small engines, such as chain saws and lawn mowers, the sensors must have very fast refresh rate and step response. The MLX90822's output step response is three times faster than other pressure sensors previously introduced by Melexis, which is sufficient to meet this demand. MLX90824 and MLX90822 help OEMs continuously reduce emissions and cope with rising oil prices by reducing fuel consumption. This series of chips ensures that cars, trucks and motorcycles meet the latest strict emission standards.
