Troubleshooting Common SoloPCB Design MistakesDesigning a printed circuit board with SoloPCB can be fast and efficient — until a mistake slows you down or breaks your prototype. This guide walks through the most common SoloPCB design errors, how to detect them, and practical fixes to get your board back on track. Whether you’re a beginner or an experienced designer, these troubleshooting tips will save time, reduce re-spins, and improve manufacturability.
1. Incorrect Schematic-to-Layout Mapping
Symptoms
- Footprints don’t match schematic symbols.
- Missing nets or components not placed in layout.
- Errors during DRC or netlist import.
Why it happens
- Mismatched reference designators or part names between schematic and PCB libraries.
- Using generic or inconsistent footprint names.
- Import/export issues when moving between schematic capture and SoloPCB layout.
How to troubleshoot
- Verify reference designators in the schematic match those in the PCB project.
- Use a consistent naming convention for parts and footprints. For example, keep footprints in the library named with manufacturer-package strings (e.g., “ATMEGA328P-TQFP32”).
- Re-generate the netlist and re-import; check SoloPCB’s import log for warnings.
- Use the “highlight net” or “select connected” features to confirm nets tied in the schematic appear the same in layout.
Quick fixes
- Rename mismatched footprints in the layout to match the schematic, or vice versa.
- Re-link components to correct footprints via the component manager.
- If a part is missing, double-check that its library file is included in the project and not accidentally excluded.
2. Wrong Footprint or Pad Dimensions
Symptoms
- Components don’t fit the board during assembly.
- Solder bridging or poor solder fillets.
- Through-hole parts don’t seat; SMT pads misaligned.
Why it happens
- Using incorrect or generic footprints not matching component datasheets.
- Inches vs. millimeters mistakes during footprint creation.
- Copying footprints from other projects without verifying pin spacing or pad shapes.
How to troubleshoot
- Cross-check every footprint against the manufacturer’s datasheet mechanical drawing.
- Measure pad sizes and pad-to-pad spacing in the PCB editor; compare with footprint drawings.
- For critical parts (connectors, crystals, power devices), print a 1:1 paper template to test mechanical fit.
Quick fixes
- Update or recreate the footprint from the component datasheet.
- Adjust pad dimensions and solder mask clearance to match recommended land patterns (IPC-7351 if available).
- Use rounded or chamfered pads where appropriate to improve solderability and reduce stress.
3. DRC (Design Rule Check) Violations
Symptoms
- Numerous clearance, trace width, or annular ring errors flagged by DRC.
- Board house rejects Gerbers or provides non-conformance feedback.
Why it happens
- Default rules not tuned to board house or design requirements.
- Multiple layers with inconsistent rules.
- Tight component placement with traces routed too closely.
How to troubleshoot
- Review DRC rule sets: minimum trace width, minimum clearance, hole sizes, and annular ring requirements.
- Align DRC settings to your PCB manufacturer’s capabilities (e.g., min track 4 mil, min clearance 4 mil, min drill 0.3 mm).
- Run DRC after major routing changes and before generating Gerbers.
Quick fixes
- Modify tracks or component placement to meet rule limits.
- Update DRC rules to match manufacturer specs if current design allows (but don’t relax rules below manufacturer minimum).
- For dense areas, use polygon pours or inner-layer routing to alleviate congestion while respecting clearances.
4. Ground and Power Plane Issues
Symptoms
- Noisy signals, erratic behavior, or EMI problems in prototypes.
- Ground loops, floating grounds, or poor thermal relief causing soldering trouble.
Why it happens
- Poorly stitched ground pours or missing thermal reliefs.
- Inadequate decoupling placement or power routing.
- Splitting ground planes accidentally with signal traces or pour islands.
How to troubleshoot
- Visualize plane connectivity: use SoloPCB’s copper pour connect mode and net highlight to confirm ground plane continuity.
- Check via stitching and thermal relief settings. Ensure vias connecting planes are placed sufficiently and follow manufacturer via-in-pad guidance if used.
- Inspect decoupling capacitors: they should be placed close to the IC power pins with short traces.
Quick fixes
- Add stitched vias to connect split pours and reduce islands.
- Use proper thermal reliefs for through-hole pads to ease soldering; apply solid or spoke connections where required.
- Re-route power traces to use thicker widths and more direct paths; place decouplers within 1–2 mm of IC pins whenever possible.
5. Poor Signal Integrity and Routing Paths
Symptoms
- High-speed signals failing (eye diagram issues, data errors).
- Crosstalk between adjacent traces, unexpected reflections, or ringing.
Why it happens
- Improper impedance control for high-speed lines.
- Long stubs, abrupt trace width changes, or 90° bends.
- Inadequate differential pair routing or mismatch in trace lengths.
How to troubleshoot
- Identify critical nets (clock lines, USB, HDMI, high-speed interfaces) and review their routing.
- Use SoloPCB’s length-match and differential pair routing features for matched traces.
- Simulate or calculate impedance where necessary; check stack-up and dielectric thickness.
Quick fixes
- Convert 90° bends to 45° or 3 x 30° bends to reduce reflections.
- Match differential pair spacing and track widths to maintain target impedance.
- Add series termination resistors or controlled-impedance traces for long lines.
6. Thermal Management Problems
Symptoms
- Components overheat, thermal stress cracking, or board warping.
- Thermal relief fails during reflow or hot spots observed during testing.
Why it happens
- Under-sized copper pours for power components.
- Poor thermal vias placement for heat dissipation.
- No heat sinks, exposed thermal pads, or inadequate copper area for dissipation.
How to troubleshoot
- Identify components with high power dissipation using a BOM and datasheets.
- Check thermal via placement and verify they connect to internal planes or bottom copper.
- Run thermal analysis if available or estimate via hand calculations.
Quick fixes
- Increase copper pour area, add more thermal vias under power IC pads.
- Add dedicated heat sinks or use thicker copper (e.g., 2 oz) for power traces.
- Redistribute heat-generating components to avoid clustering.
7. Silkscreen Overlaps and Manufacturing Marks
Symptoms
- Component designators printed over pads, SMD pads or vias.
- Confusing silkscreen or missing markings after board house processing.
Why it happens
- Silkscreen layer placed without accounting for solder mask openings or pad clearance.
- Designer forgot to clip silkscreen from exposed pads or assembly areas.
How to troubleshoot
- Inspect silkscreen layer with board house production guidelines. Highlight pads and check for overlapping text.
- Use SoloPCB’s “clip silks” or mask expansion tools to automatically remove silkscreen from pad areas.
Quick fixes
- Move reference designators away from pads or reduce font size.
- Remove silkscreen from areas with exposed copper and add assembly drawings for clarity.
8. Incorrect Layer Stack-up and Via Usage
Symptoms
- Impedance mismatches, manufacturing difficulty, or unexpected signal behavior.
- Excessive use of blind/buried vias increasing cost or causing fabrication issues.
Why it happens
- Not defining a layer stack tailored to the design (signal, plane, impedance layers).
- Using blind/buried vias unnecessarily or without consultation with the board house.
How to troubleshoot
- Confirm stack-up settings in the PCB project (copper thickness, dielectric thickness).
- Consult your fabricator for recommended stack-ups and via capabilities.
- Re-evaluate if microvias or blind vias are necessary, or if through vias suffice.
Quick fixes
- Simplify the stack-up where possible: use standard 4- or 6-layer constructions to reduce cost.
- Move critical traces to appropriate layers (e.g., return path on adjacent plane).
- Convert blind/buried vias to through-vias if acceptable for signal and cost.
9. BOM and Component Sourcing Errors
Symptoms
- Wrong part values ordered, footprints not matching purchased parts, or parts out-of-stock at assembly time.
- Extended lead times or last-minute substitutions.
Why it happens
- Inaccurate BOM entries, missing manufacturer part numbers, or ambiguous component descriptions.
- Not verifying package alternatives or distributor stock before finalizing BOM.
How to troubleshoot
- Generate a detailed BOM with manufacturer part numbers (MPNs), footprints, and alternate sources.
- Cross-reference footprints with supplier mechanical drawings and distributor package photos.
- Use a parts management tool or order small sample batches to validate parts.
Quick fixes
- Update BOM with correct MPNs and acceptable alternates.
- Lock footprints to verified parts; note any special assembly instructions in the BOM.
10. Gerber, Drill, and Fabrication File Mistakes
Symptoms
- Board house rejects Gerber files or manufactures boards with missing layers, flipped layers, or misaligned drill outputs.
- Incorrect panelization or fabrication file settings leading to extra costs.
Why it happens
- Incorrect Gerber generation settings, wrong units, or missing layer exports.
- Not running an internal CAM or Gerber viewer check before upload.
How to troubleshoot
- Always preview Gerbers in a reliable Gerber viewer. Check layer stacking, drill alignment, and board outline.
- Verify units (mm vs. inches), zero suppression settings, and file format (RS-274X recommended).
- Confirm solder mask and paste mask layers export correctly and overlay matches pads.
Quick fixes
- Re-generate Gerbers with correct export options and re-verify.
- Include a README or fabrication notes indicating board thickness, copper weight, and special requirements.
- Use the board house’s preferred file checklist to ensure compatibility.
Final Checklist Before Submission to Fabrication
- DRC clean: No unresolved DRC violations.
- Footprints verified: All footprints checked against datasheets.
- Silkscreen clipped: No text overlapping exposed pads.
- Power/Ground continuity: Planes and pours stitched properly.
- Critical net routing: High-speed lines length-matched and impedance-considered.
- Gerbers validated: Opened and inspected in a Gerber viewer.
- BOM finalized: MPNs and alternates confirmed.
Troubleshooting SoloPCB mistakes is mostly about methodically verifying assumptions — footprints, rules, layers, and manufacturability. Fix issues one class at a time, re-run checks, and keep the board house’s limits in mind. If you want, I can review a specific SoloPCB project file or Gerber set and point out likely problems.
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