SMD PCB Assembly Services
Precision surface mount assembly for complex electronics. Support for 01005 components, 0.3mm fine pitch, and BGA/X-ray inspection. 24-hour turnaround available with full IPC-A-610 Class 2/3 compliance.
Why SMT Matters for Modern Electronics
Surface Mount Technology (SMT) has replaced through-hole technology as the standard for electronics manufacturing due to its density and automation potential. However, not all SMT lines are equal. We focus on the capabilities that impact yield and reliability in the field: precise stencil printing, automated optical inspection (AOI) at every stage, and X-ray verification for hidden joints.
Advanced Component Support
- Chip Scale: Down to 01005 (0402 metric) passives
- Fine Pitch: 0.3mm pitch for QFP/QFN and ICs
- BGA/CSP: Full support with X-ray inspection
- Connectors: Micro-coax, board-to-board, and mezzanine
Process Control
- Solder Paste Inspection (SPI): 3D volume measurement pre-reflow
- Automated Optical Inspection: Post-placement and post-reflow
- Profile Verification: Thermal profiling for every unique PCB
- Moisture Sensitivity: Baking and handling per IPC/JEDEC J-STD-033
Capability Comparison
We publish specific tolerances because vague specifications like "high precision" do not help engineers design for manufacturability. Below is how our standard capabilities compare to typical industry benchmarks.
| Parameter | Standard | Our Capability | Industry Benchmark |
|---|---|---|---|
| Min Component Size | 0603 | 01005 | 0402 |
| Placement Accuracy | ±0.05mm | ±0.025mm @ 4σ | ±0.05mm |
| Fine Pitch IC | 0.5mm | 0.3mm | 0.5mm |
| BGA Inspection | Visual/X-Ray (Optional) | 100% X-Ray for BGAs | Visual Only |
| Solder Paste Check | Visual | 3D SPI (Area 85-115%) | 2D SPI |
| Lead Time (Proto) | 5-7 Days | 24 Hours | 3-5 Days |
SMT Assembly Workflow
Our process is designed to catch errors before they become soldered defects. Unlike shops that only inspect at the end, we verify at every critical transition point.
01
Data Preparation & Stencil
Gerber and centroid files are processed to generate laser-cut stainless steel stencils (electropolished) for precise paste deposition.
02
Solder Paste Printing
Solder paste is printed using high-precision printers. 3D SPI verifies volume, height, and alignment before the board moves on.
03
Pick and Place
High-speed mounters place components from 0402 to fine-pitch QFPs. Feeders are automatically calibrated to ensure pick-up accuracy.
04
Reflow Soldering
Boards pass through a 10-zone nitrogen reflow oven. Thermal profiles are optimized per PCB density and layer count to prevent tombstoning.
05
Inspection & Test
Post-reflow AOI checks for bridges, offsets, and missing components. BGAs go through X-ray. Flying probe test validates electrical continuity.
06
Final Assembly & Pack
Through-hole components are hand-soldered or wave-soldered if required. Boards are cleaned (no-clean or aqueous), inspected, and ESD-packed.
Case Study: Industrial IoT Controller
Challenge
Client required a compact 4-layer PCB with a 0.4mm pitch BGA processor and 01005 decoupling capacitors. Previous supplier had a 15% yield loss due to solder bridging under the BGA.
Solution
We implemented a stepped-stencil design with micro-apertures for the BGA pads and reduced paste volume for the 01005s. 100% X-ray inspection was performed on every unit to verify void ratios were under 5%.
Results
First article yield increased to 100%. Production yield stabilized at 99.8%. Client reduced total cost of ownership by eliminating rework labor and board scrappage.
Frequently Asked Questions
What is the minimum order quantity (MOQ) for SMD PCB assembly?
Our MOQ starts at 1 piece for prototype assembly. We do not have setup fees for standard SMT processes, making it cost-effective for engineering samples and low-volume pilot runs.
What files are required for a quote and production?
We require Gerber files (RS-274X), a Centroid or Pick-and-Place file, and a BOM (Bill of Materials) in Excel or CSV format. For assembly projects, please specify component designators and any substitution allowances.
Do you support BGA and fine-pitch component assembly?
Yes, we support BGA assembly with pitch down to 0.4mm and QFN/QFP fine-pitch components down to 0.3mm. All BGAs undergo X-ray inspection to verify void ratios and alignment per IPC-7095 standards.
What are your typical lead times for SMT assembly?
Standard lead time is 5 to 7 business days. 24-hour and 48-hour expedited turnaround options are available for prototypes if components are in stock or provided by the customer.
Can you source components for my assembly project?
Yes, we offer turnkey PCB assembly with component sourcing. We maintain supply chains with major distributors (Digi-Key, Mouser, Avnet) and can source authorized or equivalent parts. We also provide consignment assembly if you prefer to supply components.
What is the difference between SMT and THT assembly?
SMT (Surface Mount Technology) mounts components directly onto PCB pads, allowing for automation and higher density. THT (Through-Hole Technology) inserts leads into drilled holes, offering stronger mechanical bonds but requiring manual or wave soldering. We support mixed-technology boards combining both.
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Ready to Assemble Your PCB?
From 01005 prototypes to high-volume production runs, our SMT lines are ready to deliver quality you can verify.
Start Your ProjectReviewed by: Engineering Team, yourpcb | Last updated: 2026-04-14