4 Layer FR4 PCB Production Record #FR4-20260106-056
| Parameter | Value | Parameter | Value |
|---|---|---|---|
| PCB Type | FR4 PCB | Quantity | 10 pcs |
| Layers | 4 Layers | Board Type | Panel PCB |
| Dimensions | 120 x 122 mm | Copper Weight | 1oz |
| Thickness | 1.6 mm | Min Track / Spacing | 3/3mil |
| Surface Finish | ENIG (Immersion Gold) | Min Hole Size | 0.2mm |
| Solder Mask | Green | Silkscreen | White |
| Stack-up | Default | Impedance Control | Yes |
This 4-layer FR-4 board (120 × 122 mm, 1.6 mm finished thickness, TG150 KB-6165F material) was produced as single-unit panels for a quantity of 10 pieces. It featured 1 oz copper on all layers, 3 mil minimum line/space, 0.2 mm minimum hole size, green solder mask, white legend, and ENIG surface finish. The order required impedance control and 100% flying probe testing with V-scoring for final separation. The tight geometries and controlled impedance made this a fine-line multilayer build.
DFM review highlighted several specification conflicts that needed resolution. Requested impedance lines of 5/5 mil for 90 ohms were not located in the files; we identified actual differential pairs and adjusted trace widths and stackup to meet the target impedance. Outer copper thickness requirements (35 ±10% µm) conflicted with the fine 3/3 mil geometries and standard 1 oz foil, so we confirmed achievable values. Solder mask bridge capability was limited on 5 mil pad spacings with 1 oz copper; we clarified acceptance criteria for potential bridge loss. Additional issues addressed included inconsistent drill tolerances, PTH hole definitions on non-connected equal-size pads, missing process tooling holes, character placement near pads, and solder mask opening on specific vias. impedance control and solder mask bridge handling were managed through customer-confirmed adjustments and file revisions.
All engineering questions were resolved prior to production release. The order completed within the 10-day delivery window using mechanical forming. Final electrical testing and quality documentation confirmed compliance with the adjusted parameters and controlled processes.
Standard multilayer solution offering practical routing density and controlled impedance for industrial and consumer electronics.
In-depth guide to the most frequent Engineering Queries (EQ) and DFM issues in Multilayer FR4 PCB (4/6/8+ layers) production. Real factory insights on stack-up confirmation, impedance control, copper balance, inner layer design, via treatment, registration, and practical prevention strategies.
| Order ID | PCB Type | Layers | Dimensions | Solder Mask | Surface Finish | Quantity | Action |
|---|---|---|---|---|---|---|---|
| FR4-20260515-068 | FR4 PCB | 14 | 244 x 267 | Green | ENIG (Immersion Gold) | 10 | View detail |
| FR4-20260505-010 | FR4 PCB | 8 | 88.4 x 90.2 | Green | ENIG (Immersion Gold) | 100 | View detail |
| FR4-20260504-095 | FR4 PCB | 8 | 281 x 100 | Green | ENIG (Immersion Gold) | 10 | View detail |
