Brushless DC motor for e.g. computer fan, has sensor and driver circuits for full wave control of each motor coil

摘要

The first sensor/drive unit (22, 21) is suitable for full-wave control of the first motor coil (23), using a first voltage in accordance with a first Hall effect signal measured through this unit (22, 21). A second sensor/drive unit (22a, 21a) is connected in series with the first, to maintain the second voltage. Additionally, the second motor coil (23a) is connected to the supply (Vcc). The second sensor drive unit similarly applies full-wave control to the second motor coil, using a corresponding second Hall effect signal. The first and second units work together to excite the coils in alternation, so turning the rotor (2c).