Patent Number: 6,310,453

Title: Drive circuit for a speed adjustable fan

Abstract: A drive circuit for a speed adjustable fan comprises a computing IC, a Hall IC, an input terminal for external signals, and a current control circuit. The drive circuit is arranged inside the fan to control the speed of the fan without the need of an external circuit. The computing IC is connected to a Hall IC and controls two transistors connecting therewith in a state of connecting and in a state of disconnecting sequentially such that two coils of the fan are alternately magnetized so as to rotate the fan. The input terminal for external signals detects the current of the external signal source and the current is regulated by the current control circuit in the process of passing through the coils to adjust the speed of the fan.

Inventors: Lin; Yu Liang (Kaohsiung, TW)

Assignee: Asia Vital Components Co., LTD

International Classification: F04D 27/02 (20060101); G05B 005/00 (); H02H 007/08 (); H02P 001/00 (); H02P 003/00 (); H02P 007/00 ()

Expiration Date: 10/30/2018