⚠️ The Problem :

When switching power to a load, many beginners use a low-side N-channel MOSFET. But in high-side switching—where the load’s ground is constant—this doesn’t work well. You’ll need a different approach to safely control power.

🛠️ The Solution :

For high-side switching, P-channel MOSFETs are a good choice, or use N-channel MOSFETs with a gate driver that boosts the gate voltage above the source. Without this, the MOSFET won’t turn on fully.

💡 Practical Example :

Imagine powering a 12V LED strip using a microcontroller (like Arduino) that operates at 5V. If you place an N-channel MOSFET on the high side, your MCU cannot pull the gate high enough. Instead, use a P-channel MOSFET with the source at 12V and gate pulled low through a resistor to turn it on.

🔢 Sample Calculation :

To ensure the P-channel MOSFET turns on:

• Vgs = Vg – Vs = 0V – 12V = -12V
  This turns on the P-MOSFET.

• Use a 10kΩ gate pull-up to 12V and a small signal NPN transistor to pull the gate low.

🛒 Product Suggestions :

✅ MOSFET

✅ Flux

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