Pcb Trace Resistance Calculator Tool

PCB Trace Resistance Formula:

\[ Resistance = \frac{18 \times 10^{-6} \times Length_{mm}}{Width_{mm} \times Thickness_{\mu m}} \]

Resistance (R):

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1. What is PCB Trace Resistance?

PCB trace resistance is the electrical resistance of a copper trace on a printed circuit board. It depends on the trace dimensions (length, width, thickness) and the resistivity of copper.

2. How Does the Calculator Work?

The calculator uses the PCB trace resistance formula:

\[ R = \frac{\rho \times L}{W \times T} \]

Where:

\( R \) — Resistance in ohms (Ω)
\( \rho \) — Resistivity of copper (18 µΩ·mm)
\( L \) — Length of the trace (mm)
\( W \) — Width of the trace (mm)
\( T \) — Thickness of the trace (µm)

Explanation: The resistance increases with longer traces and decreases with wider or thicker traces.

3. Importance of Trace Resistance Calculation

Details: Calculating trace resistance is crucial for power distribution, signal integrity, and thermal management in PCB design.

4. Using the Calculator

Tips: Enter trace length in mm, width in mm, and thickness in µm. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical copper thickness in PCBs?
A: Standard 1 oz copper is about 35 µm thick. 2 oz copper is about 70 µm.

Q2: Why is copper resistivity 18 µΩ·mm?
A: This is the resistivity of copper at room temperature (20°C). It varies slightly with temperature.

Q3: How does temperature affect resistance?
A: Resistance increases with temperature (positive temperature coefficient for copper).

Q4: When is trace resistance most important?
A: Critical for high-current traces, precision analog circuits, and long signal paths.

Q5: Can I use this for other metals?
A: No, this uses copper's resistivity. For other metals, use their specific resistivity values.