Recently, Southchip officially released the optical image stabilization (OIS) voice coil motor driver chip SC29111. This chip achieves complete closed-loop control and can support three-axis stabilization compensation. It provides a full-link, high-precision solution from perception to execution for camera modules of smartphones, tablets, and wearable devices, marking a breakthrough in the high-endization of Southchip in the field of optical stabilization. 

Image evolution, OIS enjoys new opportunities for development 

As consumers' demands for image quality in mobile photography, especially in low-light and dynamic scenarios, continue to increase, optical image stabilization has become an indispensable core function for high-end imaging experiences and is rapidly penetrating into broader markets such as AI glasses, drones, security surveillance, and virtual reality; the deep integration with AI algorithms has also brought new opportunities for industry development. 

The optical image stabilization system uses a micro sensor to monitor the movement status of the device in real time, and the drive system quickly adjusts the optical components to counteract the impact of shake on image quality. Among them, the performance of the drive chip directly determines the response speed, accuracy, stability and power consumption of the stabilization, and has become the core technology of the OIS system. Market data shows that the global sales of OIS optical image stabilization drive market reached 689 million US dollars in 2024, and is expected to reach 934 million US dollars in 2031, with a compound annual growth rate of 4.5%. 

Full-link closed-loop control, achieving precise anti-shake function 

Southchip Technology's SC29111 integrates a Hall sensor, a digital PID controller and an H-bridge motor driver on a single chip. It enables a complete control loop of "perception - calculation - execution", significantly simplifying the design of peripheral circuits and providing a new solution for OIS with higher precision, smaller size and faster response. 

●  At the sensing end, the built-in Hall sensor can capture the slight vibrations of the camera module in real time and feed the information to the computing end. Besides the traditional two axes (X-axis & Y-axis), it also supports compensation for the rotational axis (Z-axis), achieving a comprehensive anti-shake effect. 

●  At the computing end, calculations are achieved through a 13-bit ADC and a PID controller, enabling algorithms such as feedforward compensation, automatic position partitioning, and loop gain adjustment. This further enhances the system's response speed, accuracy, and reliability. 

●  At the execution end, the integrated H-bridge current driver supplies power to the voice coil motor (VCM), with an output current of up to ±160mA. The voice coil motor does not require traditional motor intermediate components such as screws, gears, and reducers. It directly converts electrical energy into mechanical energy and has a simple control method. Additionally, the integrated 12-bit DAC employs current soft landing technology to ensure a smooth transition of the driving current and avoid secondary vibrations caused by sudden start and stop. 

Efficient design, ultimate performance 

To meet the real-time requirements of high-end applications, SC29111 supports the I3C standard with a communication rate up to 12.5 MHz and is compatible with the 3.4 MHz I2C mode, ensuring low latency in the exchange of instructions and data between the processor and the driver chip. Additionally, the chip provides a 48-byte user-programmable MTP memory and 3 groups of PID coefficients that can be quickly switched, allowing customers to deeply customize and quickly optimize according to the characteristics of different camera modules, accelerating product launch. 

The operating voltage range of SC29111 is 2.2V - 3.6V, and it is equipped with comprehensive protection functions such as magnetic bias calibration, coil resistance measurement, temperature monitoring and under-voltage lockout, ensuring stable operation in various complex environments. The package adopts WLCSP-6, with a size of only 0.59mm * 2.24mm, achieving an extremely compact board area, thereby releasing space for the increasingly precise camera module design.