What is a Driver?

What is a Driver?

It is an inverter circuit that drives a motor.
For example, a three-phase small motor has 6 power elements and 6 diodes. The power elements have transistors, FETs, IGBTs, etc.
Since the actual motor is driven by a high voltage and current, a drive circuit, which converts the PWM output of the control circuit to high voltage and large current, is required.


A pre-driver is required since a high drive current supporting around 12 volts is required to drive power elements such as FETs and IGBTs that drive the motors.
A low power motor with low voltage can be driven without a pre-driver.

  • FET : Field Effect Transistor (Field Effect Transistor)
  • IGBT: Insulated Gate Bipolar Transistor (Insulated Gate Bipolar Transistor)
  • IPD : Intelligent Power Device (Power element is modularized as an inverter)

Chapter 3 Technical Explanation of Brushless Motor

Technical Explanation of a Brushless Motor
What is PWM?
What is an Inverter?
Position Detection by a Hall Sensor
Position Detection by an Induced Voltage
What is a Square-Wave Drive?
What is a Sine-Wave Drive?
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