Define Your Exact PCB Requirements
Specify layer count, material, thickness, copper weight, surface finish, trace/space, hole size, impedance control, and IPC standard before contacting any supplier.
Layer Count: Match stack-up to signal integrity needs; avoid over-engineering.
Material: FR-4 TG150 for standard designs; Rogers or Isola for RF/microwave.
Thickness: Standard is 1.6 mm; match enclosure constraints precisely.
Copper Weight: 1 oz default; increase only where current density demands it.
Surface Finish: HASL for cost-sensitive boards; ENIG for fine-pitch components or wire bonding.
Trace/Space: Minimum 0.15 mm unless impedance or HDI justifies tighter tolerances.
Hole Size: Mechanical drill minimum 0.3 mm; laser via 0.1 mm max.
Impedance Control: Specify dielectric constant, stack-up, and target impedance; request controlled impedance reports.
IPC Standard: IPC-A-600 Class 2 for commercial; Class 3 for aerospace/medical.
Prepare Production Files Correctly
Submit Gerber RS-274-X or ODB++ with separate layers clearly named. Include NC drill files, BOM (Excel or CSV), CPL (pick-and-place), and silkscreen with polarity marks.
Common errors:
Missing soldermask expansion causing open shorts.
Silkscreen overlapping pads; fix in design rule check (DRC).
Drill files not matching Gerber holes; cross-verify in CAM software.
BOM missing reference designators; causes assembly delays.
DFM Check & Manufacturer Capability Matching
Run DFM using vendor-specific rules, not generic settings. Key checks: annular ring ≥ 0.05 mm, soldermask dam ≥ 0.08 mm, minimum text height 1 mm.
Verify factory capability:
Request recent capability report with actual tolerance data.
Ask for sample photos of similar-layer boards.
Confirm impedance test coupons on prototype runs.
Avoid vendors quoting below industry-standard tolerances without evidence.
Order Placement & Specification Confirmation
Review quote breakdown: material cost, setup fee, tooling, testing, shipping. Clarify lead time—prototype vs mass production differ significantly.
Key points:
MOQ: Prototype houses often accept 5–10 pcs; volume runs start at 50–100.
Shipping: Use DHL/FedEx for prototypes; sea freight for bulk to cut cost.
Payment: TT for large orders; PayPal/credit card for samples.
Confirm all specs in writing; request engineering confirmation before production.
Quality Control & Receiving Inspection
Inspect critical items immediately upon receipt:
Visual: No misaligned layers, lifted pads, or soldermask defects.
Electrical Test: Verify netlist continuity; request E-test report.
Impedance: Review test coupon data if specified.
Warpage: ≤ 0.75% per IPC-A-600.
Hole Quality: No barrel cracking or resin smear under microscope.
Reject criteria: Any open circuit, incorrect hole plating, or missing impedance control invalidates the batch.
Conclusion
Precise specification upfront prevents costly re-spins. Validate manufacturer capability with real data, not marketing claims. Inspect to IPC standards before payment release.
Email: all@poe-pcba.com
Whatsapp: 85292069596
Tel: 0755-25312250/ +8613798543496
Factory Address: Floor 3, Jinyuan Industrial Park, No. 56, Tangtou Avenue, Shiyan Town, Baoan District, Shenzhen China
