TI BLDC dedicated drive control chip or assistance in the development of highly integrated and insensitive FOC

    As a synchronous motor, BLDC is highly suitable for use in mobile products due to its high torque density. Especially in recent years, there have been many applications of BLDC in rapidly developing industries such as drones, robots, and electric vehicles.

    Because BLDC can make the Counter-electromotive force waveform trapezoidal, it is possible to use a DC voltage with rectangular waveform to generate a rotating magnetic field with low torque ripple, and rectangular voltage is easy to generate.

    However, due to the end market‘s need not only for motors to achieve high efficiency and multifunctional control, but also to achieve low noise and vibration control effects while pursuing high speed. These high standard performance requirements have put forward stricter requirements for control chips. More and more high-performance motor drive control chips are emerging under the two major opportunities of high market demand and high performance standards.

    For motor drive control specialized chips, if a single chip has higher device or functional integration, it can greatly simplify peripheral devices and circuits in application. This is also crucial for the overall reliability of BLDC.

    Recently, Texas Instruments released two BLDC drivers, MCF8316A and MCT8316A. Although it has not yet officially started to be released, it can be seen from the information disclosed so far that its performance is powerful.

    MCF8316A and MCT8316A integrate real-time control functions and up to 18 discrete components, including MOSFETs. MCF8316A is a sensorless magnetic field oriented control motor driver that intelligently extracts motor parameters; MCT8316A is a sensorless trapezoidal control motor driver that does not require a microcontroller interface and has high integration, thus simplifying the system.

    It is reported that MCF8316A includes a patented precision automatic Dead time compensation technology. This technology can compensate for current distortion and greatly optimize the acoustic performance of the motor. MCT8316A reduces BLDC noise through different trapezoidal control techniques.

    These two new products integrate three gate drivers and six high and low side MOSFETs, each with a conduction resistance of 50m Ω. The advantages of single core high integration can be seen from Texas Instruments‘s advanced BLDC motor drive performance. The two products can provide up to 70W power and 8A peak current in 12V and 24V systems. The embodiment of high integration is not limited to these. Low voltage drop (LDO) regulators, DC/DC buck regulators, and current detection amplifiers are all integrated in a single core, eliminating up to 18 discrete components. For low-voltage energy-saving systems, these two products should bring the most ideal choice.

    When the motor driver integrated with sensorless control function is used for real-time control, Hall effect sensor is not required in the motor, so the system reliability can be improved and the total cost of the system can be reduced. The cost reduction brought about by full integration of a single chip is also highly valued by downstream customers.

    In terms of BLDC motor control algorithm, it is also updated generation by generation. With the increasing requirements for motor control performance year by year, the BLDC control algorithm has also transitioned from square wave control to inductive SVPWM, and then to FOC. The sensorless FOC control algorithm has now established a dominant position in major manufacturers, mainly because FOC can achieve motor control goals such as high efficiency, low vibration, low noise, and high response speed to the greatest extent possible.

    The above two TI products are both based on the Field Oriented Control (FOC) control method.

    At present, the trend of BLDC motor drive chip industry technology towards single core high integration and sensorless FOC control is clear. How BLDC drive chip manufacturers can achieve breakthroughs in high efficiency, low energy consumption, and stability under the opportunity of market expansion will be the key to winning the market.