1. What is PCB Trace Inductance?

Definition: This calculator estimates the inductance of a PCB trace based on its length and width.

Purpose: It helps electronics engineers and PCB designers understand and account for trace inductance in high-speed circuit designs.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( L \) — Trace inductance (nanohenries, nH)
• \( length \) — Trace length (millimeters, mm)
• \( width \) — Trace width (millimeters, mm)

Explanation: The formula approximates the partial self-inductance of a straight rectangular conductor trace.

3. Importance of Trace Inductance Calculation

Details: Proper inductance estimation is crucial for signal integrity, power distribution network design, and minimizing electromagnetic interference (EMI).

4. Using the Calculator

Tips: Enter the trace length and width in millimeters. Both values must be > 0. The result is given in nanohenries (nH).

5. Frequently Asked Questions (FAQ)

Q1: Why does trace inductance matter?
A: Trace inductance affects signal quality, causes voltage drops, and can lead to ringing and overshoot in high-speed circuits.

Q2: How does width affect inductance?
A: Wider traces have lower inductance. Doubling the width reduces inductance by about 30-40%.

Q3: What about trace thickness?
A: This formula assumes standard 1 oz/ft² copper (35 μm). Thickness has minimal effect compared to length and width.

Q4: Does this work for curved traces?
A: No, this formula is for straight traces. Curved traces have slightly higher inductance.

Q5: What's a typical trace inductance value?
A: For a 10mm long, 0.2mm wide trace, inductance is typically 7-10 nH.