Best system integration for sensorless BLDC applications

Melexis: December 4, 2008 - Ieper, Belgium, Melexis launches it’s first member of the second generation of integrated BLDC Motor Controllers: the MLX81200. This new product features TruSense and SineDrive technologies opening new doors for system integration of automotive BLDC motor applications.

TruSense technologies combine reluctance measurement with BEMF sensing for detection and tracking of the rotor position allowing a robust motor operation in a wide dynamic range in harsh environments.

This Melexis second generation sensorless BLDC motor controllers feature dedicated Hardware blocks as well as patented motor control algorithms to guarantee fail safe and robust sensorless operation under stringent automotive conditions. On the fly rotor position sensing allows fast start up to nominal speed within 70ms. The patented BEMF (Back Electromotive Force) sensing using a phase integrator enables operation from ultra low to high motor speeds under fast varying load conditions.

The SineDrive motor control allows shaping the motor current to optimize efficiency and torque ripple for each motor, especially important for applications like engine cooling fans and HVAC blowers. Furthermore sensorless Sinewave motor control also reduces audible noise, conducted and radiated emissions simplifying the motor control.

The MLX81200 enables new applications in the world of sensorless BLDC motors. The reliable and wide dynamic operating range, the very low speed operation capabilities – reducing battery drain during engine stop condition – and the high integration make the MLX81200 the ideal solution for water pumps and transmission oil pumps in hybrid powertrains. Additionally BLDC fuel pumps, active suspension control, engine cooling fans and HVAC blowers benefit when using the new Melexis device.

The MLX81200 combines a 16 bit microcontroller with a high voltage analog periphery for BLDC motor control allowing smallest application PCBs with only a few external discrete components. It includes, 30 kB Flash program memory, 2 kB SRAM, 128 B data EEPROM, voltage regulator, on chip RC oscillator, predriver for directly driving 6 n-channel power FETs, highly accurate shunt current sensing, independent analog watch dog, high voltage I/Os and several diagnostic functions for a fail/safe operation.

It is available in QFN48 and TQFP48 7*7mm packages, and has been qualified up to 150C ambient temperature, making it an ideal fit for under the hood applications.

Samples and full development kit are available.