Micronas has introduced the the HAL 2810 as a member of the HAL 28xy sensor family. It is a linear Hall-effect sensor that includes a programmable microcontroller and a LIN bus 2.0 interface. The device is a smart sensor, integrating the sensing element, all necessary compensation functions, digital signal processing as well as full LIN bus connectivity. This reduces system cost and increases reliability, a key feature in networking automotive systems.
Micronas' new family of sensors is suitable to replace potentiometers in automotive applications. The sensors can be used for angular measurements such as in fuel-level sensing and for linear movement such as in seat-track position. In particular, the HAL 2810 is suited for passenger weight detection. The HAL 2810 measures the force on the seat attachment points and determines passenger weight based on these measurements.
The HAL 2810 is a complete single-chip sensor solution integrating a LIN bus physical layer. The sensor itself is accurate. It offers 12-bit resolution and features both spinning-current and second-order temperature compensation over a range of -40 to 140 °C. Included on-chip with the sensor is an 8-bit microcontroller with boot ROM, EEPROM, RAM, and the LIN bus slave interface. The LIN bus interface is fully compatible with LIN Specification Package 2.0, and supports data rates of 10.4 kbps and 20 kbps. The boot ROM includes firmware to drive the LIN bus. Micronas included the physical interface and overvoltage and reverse-voltage protection on all three pins, so the device can be connected directly to the bus.
The device is user-programmable via the LIN bus, so any LIN tool can be used to program the sensor. Along with the HAL 28xy, Micronas offers an easy-to-use application kit containing a programming board, LabVIEW programming software and the necessary source code. Key application variables such as magnetic field range, sensitivity, offset, and the temperature coefficients of sensitivity and offset can be adjusted by programming the non-volatile memory. The sample rate can be programmed from 27 to 54 samples per second. Besides the 32-bit LIN serial number, the HAL 2810 includes a user-programmable 12-bit sensor ID register. HAL 2810 samples are available in a TO-92UT package rated for operation from -40 to +140°C.
