The MLX90807 and MLX90808 integrated, relative and absolute pressure sensor dies from Melexis use CMOS technology, which is combined with MEMS bulk micromachining. Each sensor die has a silicon membrane with piezoresistors to transform the stress induced by pressure into an electrical signal. An analogue signal chain interacting with a digital core, including programmable memory, allows complete calibration on chip to achieve an optimised transfer function over the desired working pressure and temperature range. The pressure sensor die covers many pressure ranges from a span of 100mbar to several bars, according to the company. The use of the sensor die is straightforward when the media to be measured is benign, like dry air found in barometric sensing or engine intake manifolds, and brake boosters. The sensors meet all automotive diagnostic requirements including broken membrane detection and short and open circuit conditions. The sensors have an overall error range of less than 1% and feature trimmable offset and sensitivity. They are programmable through the connector and have a 5V analogue ratiometric output. The output of the sensors are proportional to the applied pressure and are protected against short-circuits at both battery terminals.
