Southchip announced the launch of its integrated solution for closed-loop motor control applications, featuring SC29251/2 series 3-phase BLDC motor control MCU and SC54232 magnetic encoder position sensor. Working in tandem, the two devices address the key challenges of traditional solutions – insufficient sensor accuracy, MCU computational bottlenecks, and high system BOM complexity – while delivering precise sensing and efficient drive for BLDC motor control systems. The chipset is well-suited for a broad range of high-end consumer electronics and robotics applications, further expanding Southchip's product portfolio.

BLDC motors, with their high efficiency, versatile control methods, and high reliability, are playing an increasingly critical role in fast-growing emerging sectors such as high-end consumer electronics, electric vehicles, and humanoid robots. According to market reports, the global market size for BLDC motor controller ICs and driver ICs is expected to reach RMB 55.6 billion by 2028.

However, the complexity of BLDC motor drive algorithms places stringent demands on computational power and response speed of the main controller, particularly in areas such as rotor position detection and coordinated current-loop/velocity-loop control. Traditional solutions often require multiple discrete chips to handle sensing, computation, and drive functions separately, which not only increases system BOM cost but also limits overall performance improvement.

As the driving core of the solution, SC29251/2 is a high-performance 3-phase BLDC motor control MCU designed for wide-voltage and high-reliability applications. It supports an 8V-18V single power supply and features 32KB Flash with ECC and 4KB XRAM with parity check. The analog front-end integrates 4 op-amps, 5 comparators, a 12-bit 13-channel ADC, and 2 DACs, flexibly supporting various current sensing and protection schemes.

SC29251/2 adopts a dual-core architecture combining a dedicated Motor Control Core (MCC) and an enhanced 8051 MCU. The MCC runs at up to 60MHz and integrates hardware-accelerated algorithms engines including FOC (Field-Oriented Control), SVPWM (Space Vector Pulse Width Modulation), MDU, LPF, and PID. It supports single-shunt, dual-shunt, and triple-shunt current sensing topologies, enabling standalone sensored/sensorless FOC and trapezoidal commutation control for BLDC/PMSM motors. The FOC engine supports sensorless operation with adaptive, sliding-mode, and nonlinear flux-linkage observers; the SVPWM engine supports 7-segment, 5-segment, and over-modulation modes.

The 8051 MCU core also runs at up to 60MHz, handling parameter configuration, communications, and user logic. The two cores operate in parallel with clear division of labor: the hardware accelerators handle the heavy lifting of vector transformation and loop control, freeing the 8051 core to manage complex communication protocols and custom protection logic. This ensures real-time control performance while freeing up Flash resources for upper-layer application and development – delivering high-performance motor control at low system cost.

SC29251 provides PWM outputs for easy connection to external driver stages, while the SC29252 integrates a 150V pre-driver with bootstrap diode to further simplify power-stage design. A single hardware platform covers sensored/sensorless, trapezoidal/sinusoidal, and FOC/trapezoidal control strategies.

SC54232 magnetic encoder is based on differential planar Hall sensing technology, integrating a Hall sensor, angle calculation, and self-calibration unit into a single chip to achieve high-precision position feedback of better than 0.3°. Unlike traditional optical encoders or switch-type Hall solutions, SC54232 uses two orthogonally placed Hall bridges to sense the rotation angle of a magnet in the XY plane, with dedicated on-chip circuitry performing amplification, compensation, and angle calculation. It offers a rich set of output interfaces – SPI, ABZ incremental output, UVW communication signals, analog voltage, PWM, and Z-axis push detection – to accommodate a wide variety of application scenarios.

The ABZ interface can replace traditional optical encoders with programmable resolution up to 16,384 pulses per revolution; the UVW interface can replace switch-type Hall sensors with programmable pole-pairs from 1 to 16; the SPI/analog/PWM interfaces allow the host MCU to read 16-bit absolute angle data; and the PUSH pin detects fast changes in the distance between the magnet and the chip, enabling contactless push-button rotary knob functionality. Alternatively, reading the internal magnetic field strength register allows Z-axis displacement detection for button-press sensing.

SC54232 simultaneously enables angle detection, speed feedback, and button interaction, supporting speeds up to 80,000 RPM with an output propagation delay of only 5μs. When paired with SC29251/2, it provides a full-link, low-latency solution from position sensing to drive execution for high-performance closed-loop control systems – particularly well-suited for robotic joint control and high-speed industrial spindles where precision and dynamic responses are critical.