AN2687 Freescale Semiconductor / Motorola, AN2687 Datasheet - Page 2

• Manufacturer Part Number: AN2687
• Description: BLDC Fan Control using the MC68HC908QT2
• Manufacturer: Freescale Semiconductor / Motorola

AN2687/D
BLDC Fan Basics
2
Let us review the basics of the BLDC fan. In
many parts such as the fan hub, axle, center bearing, stator coils, fan frame,
permanent magnets, and Hall effect sensor.
In
switch-on with positive magnetic field and switch-off with negative magnetic
field. It provides the commutation signal to drive the stator coils and let the
motor rotate.
Compared with a brush DC (BDC) fan, the BLDC fan does not have a rotating
brush assembly, hence the BLDC motor is more reliable. In addition, the
relatively compact size of the BLDC is due to its superior structural integrity and
thermal dissipation. Therefore, the BLDC fan is preferred in more thermal
complex applications.
Figure
Freescale Semiconductor, Inc.
BLDC Fan Control using the MC68HC908QT2
For More Information On This Product,
2, The Hall effect sensor provides the digital output that indicates the
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Figure 2. Commutation of the BLDC Fan
Stator Coil
Figure 1. The Structure of BLDC Fan
Hall Effect
Sensor
Hall Effect Sensor
Control IC
Stator
Coil
Axle
Fan Hub
Figure
Permanent
Magnets
1, the BLDC fan consists of
To MCU
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