The present invention relates to an average current controller, an average current control method and a buck converter using the average current controller. According to the present invention, each sense amplifier is used to precharge at least two bit lines, then to read one memory cell in one of the precharged bit lines. Optional attachments are used to collect waste products generated by rotary motion machine. Transport protocol units are autonomous modules. Further, the securingly connection between the enclosing part, the arresting part, and the locking retainer also enhances the structural strength, thereby reducing the rotational shaking of the pivotal axle.