Melexis continues to make major advances in tire pressure monitoring system (TPMS) technology with the introduction of its 3rd generation TPMS IC - the MLX91804.
Supplied in a robust 14-pin DFN type lead-less package, this product has a 60% smaller footprint and draws 3 times lower sleep mode current than any competing TPMS IC on the market. It incorporates a sophisticated microcontroller and MEMS-based pressure sensing element, as well as energy efficient 315/433 MHz wireless transmitter (supporting data rates up to 150 kbits/s) and 125 kHz receiver for communication with the vehicle’s relevant electronic control unit (ECU). A 16 kB embedded program memory is included for the storing of custom application data/libraries. In addition, there is a built-in single or dual axis high-g range accelerometer to support all market available wheel sensor auto-location functionalities.
The combination of minimal footprint and high degrees of integration offered by the MLX91804 means that a significant reduction in PCB size can be realised. Likewise, the device’s low power consumption (in sleep mode as well as when fully operational) permits a downsizing of the specified battery. All this results in a smaller size and lower weight sensor module. Together with high-g range and fast data acquisition accelerometer, it also represents a step closer to the tire mounted sensor (TMS) implementations that automotive Tier 1 suppliers are looking to use in the future. Best in class precision and low power fast pressure measurements allow extra new features to be implemented like tire filling assistant without a visible impact on battery life. The -40°C to 125°C operational temperature range and strong resilience to shock (10000g) allow the MLX91804 to deal with a harsh in-tire environment.
