Portable, feature-rich, high performance and small size is a significant trend in most electronic products. Heat generated by these electronic products (such as laptops) generated aroused more and more attention. Use "24V DC Cooling Fan" Prevention is still the most common electronic equipment from overheating, the most effective way. In order to achieve the fast-changing electronics products specification, people need to use microcontroller-based (MCU) intelligent variable speed control, brushless DC (BLDC) fans.