Project Design Issues
1:16
Considering trace width for PCB.
Accessing knowledge base.
Gathering guideline information for PCB trace width.
Clarifying via recommendations.
Summarizing current recommendations.
Clarifying width recommendations.
Short answer: increase it. For 2 A on the default 1 oz (35 µm) copper, 0.6 mm is too narrow for continuous current if you want a modest temperature rise. Use at least 1.0 mm, and prefer 1.2–1.5 mm if you have room. Add a copper pour on the same net to further reduce resistance and temperature.
Practical recommendations
- 1 oz outer layer:
- 2 A continuous: 1.0–1.5 mm trace width (choose 1.2–1.5 mm if ambient is warm, runs are long, or there’s little airflow).
- Short bursts or low duty: 0.8–1.0 mm may be acceptable, but only with margin.
- 2 oz outer layer:
- 2 A continuous: 0.6–0.8 mm is typically fine; use 1.0 mm+ if you can.
- Use pours where possible:
- Replace long “thick traces” with a same-net polygon pour to drop resistance and spread heat.
- Vias in high-current paths:
- If you must swap layers, do not rely on a single via. Use at least 3 vias of 0.3–0.4 mm finished hole (or 2 of 0.5 mm) in parallel per 2 A transition.
- Stitch pours with a via grid near MOSFETs, connectors, and the buck output.
- Clearance:
- Keep ≥0.5 mm clearance from high-current copper to sensitive signals; more if you expect large dI/dt.
- Thermal:
- Widen at pads (teardrops or small copper “flares”), especially at terminal blocks and MOSFET drains/sources.
- Avoid neck-downs at vias and component pads; step width gradually.
Flux setup tip
- Create a net class (e.g., HighCurrent_2A) and set:
- Width: 1.2–1.5 mm (1 oz), or 0.8–1.0 mm (2 oz)
- Clearance: 0.5 mm
- Via style: multiple 0.3–0.4 mm finished vias in parallel
- Assign this net class to your 2 A paths (e.g., from buck output to solenoids/relay feed).
Rule of thumb summary
- 2 A on 1 oz: 1.0–1.5 mm
- 2 A on 2 oz: 0.6–0.8 mm
- Prefer pours over long fat traces; add parallel vias for any layer change.
If you tell me your copper weight, maximum allowable temperature rise, and approximate run length, I can tighten these numbers further.
Check my copper weight
Estimate width for my run
Find a wide-net rule
Review my current path
65 days
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