Description
Protect your circuits from accidental reverse polarity with almost no voltage loss.
The Reverse Polarity Protection Board v2 uses a P-channel MOSFET instead of a conventional series diode, providing highly efficient reverse polarity protection while introducing only a very small voltage drop.
Unlike diode-based protection, which always sacrifices part of the supply voltage, a properly selected MOSFET behaves like a very small resistor once fully turned on. More of the supply voltage reaches your circuit, less power is converted into heat, and higher currents can be handled efficiently.
The PCB is intentionally configurable, allowing the same design to be used in applications ranging from 5 V to 48 V simply by selecting suitable components.
Why Use a P-Channel MOSFET?
Traditional reverse polarity protection often uses a silicon or Schottky diode.
Although simple, every diode introduces a forward voltage drop.
A P-channel MOSFET dramatically reduces this voltage loss, making it particularly attractive for:
- Battery-powered equipment
- Embedded systems
- Laboratory power supplies
- Industrial electronics
- Automotive projects
- Robotics
- Sensor systems
A Configurable Building Block
Rather than being designed for a single supply voltage, this PCB is intended to become a reusable front-end power module for many different projects.
By selecting an appropriate:
- P-channel MOSFET
- Gate resistor
- Optional zener diode
the board can be adapted for:
- 5–12 V systems
- 12–24 V systems
- 24–48 V systems
making it suitable for hobby, educational and professional applications alike.
Features
- Ultra-low voltage drop
- Reverse polarity protection
- Configurable for 5 – 48 V systems
- Optional gate protection zener diode
- Through-hole construction
- Breadboard-friendly pin headers
- Compact 36 × 31 mm PCB
- Large input and output terminals
- Reusable front-end power module
- Ideal for permanent installations and prototype systems
Companion Documentation Included
The board is accompanied by a comprehensive 22-page guide that explains not only how to assemble the PCB, but also the theory behind the circuit and how to configure it for different supply voltages.
Topics include:
- How the circuit works
- The MOSFET body diode explained
- Choosing a MOSFET from a datasheet
- Which datasheet parameters actually matter
- Comparing PMOS, Schottky and silicon diode protection
- Three complete design examples
- Selecting the zener diode
- Calculating the gate resistor
- Checking resistor and zener power dissipation
- Recommended component values
- PCB layout and assembly sheet
Whether you’re building your first reverse polarity protection circuit or adapting the design for a higher-voltage application, the documentation provides a practical step-by-step guide.
Typical Applications
The Reverse Polarity Protection Board can be used wherever accidental supply reversal is possible, including:
- Prototype circuits
- Breadboard power distribution
- Battery-powered equipment
- Embedded systems
- Laboratory projects
- Industrial control electronics
- Automotive accessories
- Robotics
- Sensor interfaces
- Amateur radio equipment
- LED lighting systems
Designed for Learning
Like the other ufelectronics.eu boards, this PCB is more than just a finished circuit.
It is designed to help users understand why the circuit works and how to adapt it to their own projects. The companion guide explains the design decisions, component selection process and practical engineering considerations behind an efficient MOSFET-based reverse polarity protection circuit.
What’s Included
- 1 × Reverse Polarity Protection Board v2 PCB (36 × 31 mm)
Components are not included.
