1. What is a PCB Trace Width Calculator?

Definition: This calculator determines the minimum trace width needed for a given current while keeping temperature rise within specified limits, based on IPC-2152 standards.

Purpose: It helps PCB designers ensure proper current carrying capacity and thermal performance of their circuit board traces.

2. How Does the Calculator Work?

The calculator uses the IPC-2152 formula:

Where:

• Width — Trace width (mils)
• I — Current (amps)
• ΔT — Temperature rise (°C)
• k — Constant (0.048 for external layers)
• a — Dimensionless exponent (0.725)
• b — Dimensionless exponent (0.44)

Explanation: The formula calculates width based on current, allowable temperature rise, and material properties.

3. Importance of Proper Trace Width

Details: Correct trace width prevents overheating, ensures reliable current carrying capacity, and maintains signal integrity in PCB designs.

4. Using the Calculator

Tips: Enter the current in amps, desired temperature rise (default 10°C), and constant (default 0.048 for external traces). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between internal and external traces?
A: External traces dissipate heat better, hence the different k values (0.048 external, 0.024 internal).

Q2: What's a typical temperature rise limit?
A: 10°C is common, but higher values (20-30°C) may be acceptable depending on application.

Q3: Does this account for copper thickness?
A: The formula assumes 1 oz/ft² copper (1.37 mils thick). For other weights, adjust accordingly.

Q4: What about high-frequency effects?
A: This calculator is for DC/low-frequency. High-frequency designs need additional considerations.

Q5: How conservative are these results?
A: IPC-2152 is more accurate than older standards, but always verify critical designs.