This part is a kind of semiconductor called APX9270.

Function of this product has Direct PWM Variable Speed Fan Motor Driver.

Manufacturers : ANPEC

Image and pinout :

Some of the text within the PDF file :

APX9270 Direct PWM Variable Speed Fan Motor Driver Features • • • • • • • Single Phase Full Wave Fan Driver Low Quiescent Current (6mA Typical) Built-in Variable Speed Function Current Limit Circuit (includes both internal and external Current Limit) Built-in Lock Protection and Auto Restart Function FG (rotation speed detection) Output Soft Switching Circuit (before phase change, enabling low-consumption, low loss and low noise drive.) Over Voltage Protection (16.5V Typical) Built-in Kickback Absorption Circuit Built-in Thermal Protection Circuit Lead Free and Green Devices Available (RoHS Compliant) General Description The APX9270 is a single phase, DC brushless motor driver with PWM variable speed control and current limit features suitable for the fan of personal compute [ ... ]

APX9270 PDF Datasheet Download