HALL EFFECT CIRCUITS ECE001. BHAVYA PURI 10801731 A6802A25. WHAT IS HALL EFFECT. Hall Effect
The Hall effect IC (integrated circuit) is a very small chip which includes many transistors. It consists of a thin layer of silicon as a Hall generator (which works better than gold) and several transistor circuits: to amplify the Hall voltage to a necessary level; to trigger output voltage with its growth; and to provide stable work regardless of the power supply voltage changes. The picture below demonstrates the Hall effect IC (between the coin and two power transistors):
The Hall effect IC is a solid state electronic device with no mechanical parts and therefore it is more reliable than a reed switch. To no surprise it is now the most widely used sensor in industrial brushless motors. Normally, however, they include a lot of other components. I tried to design a motor on a Hall effect switch with minimum parts based on the same unified mechanical design and it worked very well.
The Hall effect switch output current is not sufficient to power this motor, therefore it also requires a power transistor. You may find information on this component at How It Works: Reed Switch Motor With A Transistor.
When the rotor spins away, magnet #1 stops affecting the Hall IC. Since the signal to the base of the power transistor has been removed, it is turned off. This disables the electromagnet.