73. N-Channel MOSFET for LED Strip PWM Driver

To control LED strip brightness, the MCU outputs a PWM (Pulse Width Modulation) signal. By varying the duty cycle, the average power to the LED strip changes, controlling perceived brightness.

An N-Channel MOSFET as a low-side switch connects the LED strip’s ground side to GND when ON, completing the circuit. The MOSFET switches much faster than a BJT, has virtually zero gate current, and has very low ON-resistance — making it ideal for PWM switching.

Critical: the MOSFET must be a logic-level type — meaning it turns ON fully with a 3.3V gate signal. Standard MOSFETs need 10V at the gate and would barely turn ON (or not at all) with 3.3V.

Required: N-Channel · Vdss ≥20V · Id ≥2A · Vgs(th) ≤2.5V · Rds(on) ≤200mΩ · SOT-23 · SMD

Go to DigiKey.com → Discrete Semiconductor Products → Transistors - FETs, MOSFETs - Single

Apply these filters:

• FET Type → N-Channel
• Technology → MOSFET (Metal Oxide)
• Drain to Source Voltage (Vdss) → 20V or higher
• Current - Continuous Drain (Id) → 2A or higher
• Vgs(th) (Max) → 2.5V or lower
• Rds On (Max) → 200mΩ or lower
• Package / Case → SOT-23-3 (TO-236)
• Part Status → Active

Important: Vgs(th) is the threshold where the MOSFET barely starts to turn ON — it is NOT the voltage for full enhancement. For reliable operation, the gate drive voltage should be at least 2× the Vgs(th). With Vgs(th) ≤2.5V and a 3.3V gate, this condition is tight but acceptable for logic-level FETs.

The filtered list will show matching parts. Before you pick one, check: Is it Active? Is stock available? Is the manufacturer reputable? Is a datasheet available?

Full checklist: How to Select a Safe, Production-Ready Component — EWskills Guide

➡ View Matching Parts — N-Ch MOSFET, SOT-23, Vgs(th)≤2.5V, Id≥2A, Rds(on)≤200mΩ