Introduction to BLDC drive circuit architecture: new applications drive the trend of high integration

1. Core components of a typical BLDC drive circuit

1. Main control chip (MCU/MPU/FPGA)

   Execute control algorithms such as FOC and six-step commutation, process sensing signals, output PWM, and implement protection logic.
2. Driver chip (Gate Driver)

   Amplify the PWM signal to drive the MOS tube, provide electrical isolation, manage dead time, and prevent the upper and lower bridges from being connected.
3. Power MOSFET

   Three-phase full-bridge switching device performs current commutation and determines the motor's torque and speed output capabilities.
4. Current sensing chip

   Real-time detection of winding current for closed-loop speed regulation, current limiting protection and torque control.
5. Position sensing chip (Hall sensor, etc.)

   Detect the rotor position to provide the basis for phase commutation; the non-inductive FOC solution can omit this device.
6. Power management chip (PMIC/LDO)

   Provide stable power supply to each module of the system.
7. Communication interface chip

   Realize interaction with host computer and system main control (I2C/SPI/UART, etc.).

2. BLDC control scheme: High integration has become a mainstream trend

1. Single chip: MCU + driver + MOS + protection highly integrated

• International: TI MCF8316C-Q1 / MCT8315A integrated driver, MOS, protection and pre-programmed FOC, no external MCU required.
• Domestic: Yuanengxin All-in-One, Smart Micro MM32SPIN023C, Sinomicro CMS32M65, etc. integrate the driver, op amp, ADC, and three-phase driver, greatly reducing the size and BOM cost.

2. The control algorithm is hardware-based, and the FOC computing power is greatly improved.

• A dedicated motor engine (ME)/hardware acceleration unit replaces pure software computing.
• Representatives: Hangshun HK32M060 (EMACC motor acceleration), Fengqi FU6812L (hardware FOC engine), with faster response and lower computing power usage.

3. Popularization of non-inductive FOC, eliminating the need for Hall sensors

• Relying on current observation and algorithms to achieve position estimation, simplify the structure and improve reliability.
• Representative: Fengxiao FT8213Q, integrated driver + MOS + protection + non-inductive FOC, suitable for highly compact scenes.

4. Vertical integration of power supply, protection and communication

• Integrated LDO, over-current/over-temperature/under-voltage protection, and I2C/SPI speed control interface.
• Representatives: Lingxin Micro LCP037A, Lingou Chuangxin LKS32MC038 series, one-stop solution to meet system needs.

5. Intelligence + SiP packaging becomes the next generation direction

• Introducing AI adaptive algorithms to achieve predictive maintenance and efficiency self-optimization.
• SiP/MCM multi-chip packaging further integrates power and control, taking into account performance and heat dissipation.

3. Market drivers and industry prospects

• Market size: In 2030, the BLDC market is expected to reach$30.86 billion，CAGR 6.5%。
• core motivation：
  1. Demand for AI server cooling, robots, and vehicle electronic controls explodes
  2. Energy efficiency policy promotes comprehensive replacement of brushed motors
  3. Integrated solutions significantly reduce development difficulty and total costs
• Material upgrade: The scheme is gradually compatible withSiC/GaNThe third generation of semiconductors further improves efficiency and power density.