Electronics

Power MOSFET Motor Control

Because of the very high input gate resistance of MOSFETs, MOSFET’s fast switching speeds, and the ease at which they can be driven makes them ideal to interface with op-amps or standard logic gates. Nevertheless, care must be taken to ensure that the gate-source input voltage is correctly chosen because when using the MOSFET as a switch the device must obtain a low RDS(on) channel resistance in proportion to this input gate voltage.

Power MOSFET can be used to control the movement of DC motors or brushless stepper motors directly from computer logic or Pulse-width modulation (PWM) type controllers. Because a DC motor offers high starting torque that is also proportional to the armature current, MOSFET switches along with a PWM can be used as a very good speed controller that would provide smooth and quiet motor operation.

Related: Metal Oxide Semiconductor FET (MOSFET)

A Simple Power MOSFET Motor Controller

Power MOSFET Motor Controller
Figure: Power MOSFET Motor Controller

As the motor load is inductive, a simple “Free-wheeling” diode is connected across the load to dissipate any back emf generated by the motor when the MOSFET turns it “OFF”. The Zener diode is used to prevent excessive gate-source input voltages.

You can also read: The Junction Field Effect Transistors (JFET)

John Mulindi

John Mulindi is an Industrial Instrumentation and Control Professional with a wide range of experience in electrical and electronics, process measurement, control systems and automation. In free time he spends time reading, taking adventure walks and watching football.

View Comments

Recent Posts

Smart Home Devices and Embedded Systems: What Instrumentation Engineers Should Know

Image source: Pexels Smart homes are no longer futuristic. They are already here, changing how…

1 week ago

Thyristor Power Converters: Function, Applications, Advantages & Disadvantages

Thyristors are semiconductor devices that tend to stay ‘ON’ once turned ON, and tend to…

1 week ago

The Future of Telecommunications: How 6G and IoT Are Redefining Connectivity

Image source: Freepik Introduction: The Evolution of Connectivity Telecommunications have come a long way since…

1 week ago

Precision Control in Industrial Heating: How Advanced Induction Systems Enhance Efficiency

Modern manufacturing demands smarter heat treatment. Specifically, factories seek greater precision, energy efficiency, and automation.…

2 weeks ago

Control Architectures for Smart EV Charging: Meeting NEC 2023, Demand Response, and Safety Standards

An Expert’s Guide to EV Load Management and NEC Compliance Smart EV charging control architectures…

1 month ago

How Residential Battery Backup Protects Your Home During Power Outages

Frequent power failures due to severe storms, aging grid infrastructure, and other unpredictable natural disasters…

1 month ago