FR120N Isolated MOSFET Module for PWM and DC Load Control

Information about this module is generated with the help of AI. The description may be incomplete, inaccurate, or subject to change.

The FR120N Isolation MOSFET Module is a compact module designed for controlling DC loads using a microcontroller, PLC, Arduino or other control system. The module combines an FR120N N-channel MOSFET with a PC817 optocoupler to provide galvanic isolation between the control circuit and the load. This electrical isolation helps reduce interference and protects the control circuit from electrical transients.

The module can be driven directly by 3.3 V or 5 V logic signals and supports PWM, making it suitable for DC motor speed control, LED dimming, heaters, solenoid valves, pumps, relays and many other DC loads. It operates as a low-side switch, meaning it switches the negative side of the load.

Although the FR120N MOSFET has a higher theoretical current rating, a continuous load of approximately 3 A to 5 A is recommended in practical applications without additional cooling. With adequate cooling, higher continuous currents can be used under suitable operating conditions.

PWM operation performs best at frequencies between approximately 100 Hz and 1000 Hz. The built-in PC817 optocoupler provides reliable electrical isolation but limits switching performance at higher PWM frequencies. For high-frequency PWM applications, a module with a dedicated MOSFET gate driver is recommended.

The signal input can be connected using pin headers or soldered directly to the PCB and is compatible with breadboards. The load output can be connected by direct wiring or through screw terminals. Two mounting holes make the module easy to install in enclosures and electronic equipment.

The module is suitable for Arduino, ESP32, ESP8266, Raspberry Pi, STM32, AVR and other microcontroller-based systems where a compact, electrically isolated MOSFET output is required.

Gate Voltage Recommended Continuous Current
3.3 V 1-2 A
5 V 3-5 A
10 V 5-8 A (with adequate cooling)

Facts.
Product name : FR120N Isolation MOSFET Module
MOSFET : FR120N
Transistor type : N-channel MOSFET
Optocoupler : PC817
Isolation : Galvanic isolation between control signal and load
Control voltage : 3.3 V or 5 V, max 24 Volt
Control signal : Digital signal or PWM
Logic : High level ON, low level OFF
PWM support : Yes
Recommended PWM frequency : Approximately 100 Hz to 1000 Hz
Recommended continuous current : Approximately 3 A to 5 A without additional cooling
Output type : Low-side switch
Input connection : Pin header or direct soldering
Output connection : Direct wiring or screw terminal
Mounting holes : 2
Module size : 23 x 16 mm
Applications : DC motors, LED lighting, solenoid valves, pumps, heaters, relays and other DC loads
Compatibility : Arduino, ESP32, ESP8266, Raspberry Pi, STM32, AVR, PLC and other microcontrollers

Included.
1 pc module.

About the product.
Weight: approx 10 gram.
Contact us if you have questions at info@pchbutik.se
Article no: 2815
Remaining stock quantity can be found under the Product details tab.
In our range since: 2026-09-21

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