Contract Manufacturing Process Flow
1. Quote & NPI Review
Submit BOM, Gerbers, and assembly drawings. Engineering team reviews DFM/DFA considerations and provides detailed quote with lead time.
2-5 Business Days2. Component Procurement
Authorized distributor sourcing, component verification, and incoming inspection. Moisture sensitive components properly stored.
1-8 Weeks (Lead Time Dependent)3. Stencil & Program Setup
Laser-cut stencil fabrication, pick & place programming, reflow profile development, and first article inspection setup.
1-2 Business Days4. SMT Assembly
Solder paste printing, automated component placement, reflow soldering with nitrogen atmosphere for optimal joint quality.
Production Rate Dependent5. Through-Hole & Manual Assembly
PTH component insertion, wave or selective soldering, hand soldering for special components, and rework if needed.
Volume Dependent6. Inspection & Testing
AOI inspection, X-ray for BGA/QFN, ICT or flying probe testing, functional test per customer specification.
Included in Production7. Final Assembly & Packaging
Conformal coating (if required), enclosure assembly, labeling, ESD-safe packaging, and documentation preparation.
1-3 Business Days8. Quality Assurance & Shipping
Final QC audit, CoC generation, lot traceability documentation, and secure shipping with tracking.
1-2 Business DaysDesign for Manufacturability Checklist
Fiducial Marks Present
Global and local fiducials for SMT placement accuracy (min 1mm diameter, 2mm clearance)
Component Spacing
Minimum 0.5mm between components for AOI access and rework capability
Pad Design
IPC-7351 compliant land patterns for optimal solder joint formation
Thermal Relief Pads
Through-hole pads connected to planes via thermal reliefs for proper soldering
Panelization
Board edges have sufficient rail width (5mm min) for handling and V-score/routing
Test Points
Adequate test points accessible for ICT/flying probe (min 0.9mm diameter)
Solder Mask Dam
Minimum solder mask web between pads (75µm for standard, 100µm recommended)
BGA Considerations
Via-in-pad filled and planarized, proper pitch and ball diameter specifications
Design Tips for Manufacturing Success
Use Standard Component Packages
Stick to common packages (0402, 0603, 0805, SOIC, QFP, QFN) to ensure availability and reduce setup time. Avoid obsolete or exotic packages that may cause procurement delays.
Component SelectionMaintain Consistent Component Orientation
Orient all polarized components in the same direction (pin 1 to the top-left). This reduces placement errors and makes visual inspection more efficient.
LayoutDesign for Reflow Profile Compatibility
Avoid mixing components with vastly different thermal mass on the same side. Large thermal mass components may require different reflow profiles.
ThermalInclude Adequate Silkscreen Reference
Clear reference designators and polarity marks improve assembly accuracy. Keep silkscreen away from pads (min 0.15mm) and ensure readability.
DocumentationPlan for Depanelization
Keep components at least 3mm from board edges for V-score, 1.5mm for tab routing. Consider mousebites for irregular board shapes.
PanelizationSpecify Clear Assembly Notes
Include detailed assembly drawings with special instructions: no-clean vs. clean process, conformal coating keep-outs, and any mechanical assembly requirements.
DocumentationConsider Moisture Sensitivity
Identify MSL (Moisture Sensitivity Level) for all components. Ensure proper storage and baking procedures are specified for MSL 3 and higher components.
QualityOptimize BOM for Second Source
Specify alternate parts where possible, especially for critical components. This protects against supply chain disruptions and potential cost savings.
Supply Chain✓ Accelerators
- • Complete documentation package
- • Standard component footprints
- • Approved vendor list flexibility
- • Previous production history
- • Stock components available
✗ Delays
- • BOM discrepancies or missing info
- • Long-lead or allocated components
- • Design changes after quote
- • Special testing requirements
- • Custom packaging needs