Switching high-current loads safely and efficiently is a key part of modern electronics design. A MOSFET load switch offers a compact, reliable solution—perfect for hobbyists and prototypers.

The Problem: Mechanical Switches Are Inefficient

Relays and mechanical switches wear out, arc under load, and are bulky. When switching high-current devices like motors or LED strips, traditional methods cause heat, sparking, or failure over time.

The Solution: Use a MOSFET as a Solid-State Switch

MOSFETs can switch large currents silently with minimal power loss. By controlling the gate with a microcontroller or logic circuit, you can efficiently manage loads up to 10A or more with ease.

Key tip: Use a low R_DS(on) N-channel MOSFET and add a gate resistor (e.g., 10Ω–100Ω) for stable switching.

Practical Example: Switching a 12V Car Fan

Say you’re controlling a 12V DC fan that draws 3A using an Arduino.

Fix: Use an IRFZ44N MOSFET, gate connected through a 100Ω resistor. Connect source to GND, drain to fan’s negative lead. Fan turns on/off via digital pin with no mechanical wear!

Sample Calculation: Power Dissipation

If R_DS(on) = 0.04Ω and current = 3A:

P = I² × R = 3² × 0.04 = 0.36W

Use a heatsink or pick a lower R_DS(on) MOSFET for higher currents.

Product Suggestion (Made in India)

Make your projects robust with locally made components:

• MOSFET Modules – For high-current switching
  Shop MOSFET Modules

• Flux Paste – Ensure clean, strong joints
  Shop Flux Paste

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