To ensure zero out-of-box failures, we offer a comprehensive testing suite tailored to project complexity:
In-Circuit Testing (ICT): Bed-of-nails electrical fixtures verifying component values, tolerances, and circuit continuity.
Flying Probe Testing (FPT): Fixtureless electrical testing suitable for high-density prototypes and small batches.
Functional Circuit Testing (FCT): Custom test jigs powering up the board to execute automated firmware loading, I/O signal simulation, RF calibration, and communication bus checks.
Environmental Stress Screening (ESS): Thermal cycling, burn-in chamber testing, and multi-axis vibration testing.

IPC-A-610 Class 3 limits BGA voiding to ≤ 15%. XinshunPCB typically suppresses voiding to < 8% to 10%. We accomplish this through: (1) Designing laser-cut electro-polished stencils with optimized aperture patterns (window pane cross-hatching for ground slugs); (2) Formulating high-activity, low-voiding Type 4/Type 5 solder pastes; and (3) Running multi-zone reflow ovens under a controlled Nitrogen (N2) atmosphere (< 100 ppm O2 residual) with tailored thermal soak zones to facilitate complete flux degassing prior to liquidus transition.

We enforce a three-tier inline automated quality inspection process to intercept defects before they can propagate:
In-Line 3D SPI (Solder Paste Inspection): Measures 100% of solder paste deposit volume, height, area, and coplanarity immediately after stencil printing, intercepting paste bridging or insufficient volume.
In-Line 3D AOI (Automated Optical Inspection): Inspects post-reflow component presence, polarity, alignment skew, tombstoning, and solder joint wetting using multi-frequency structured light.
High-Resolution 3D Micro-Focus X-Ray: Penetrates non-visible joints beneath BGA, CSP, and QFN packages to inspect internal wetting, bridging, and solder ball void percentages.

Our high-speed automated placement lines (Panasonic NPM / Yamaha YSM series) achieve high-accuracy placement with repeatability within ±0.03 mm (Cpk ≥ 1.33). We reliably assemble micro passives down to 01005 (0402 metric) and fine-pitch packages down to 0.30 mm pitch micro-BGAs, WLCSPs, and 0.35 mm pitch QFNs. Lead coplanarity and component alignment are verified in real time using multi-angle laser optical sensors prior to board touch-down.

We offer flexible procurement and assembly models to match your supply chain strategy:
Full Turnkey: XinshunPCB manages the entire lifecycle—fabricating bare boards, procuring 100% genuine components from authorized distributors (e.g., Digi-Key, Mouser, Arrow, and original factory direct lines), fabricating solder paste stencils, SMT/THT assembly, and final functional verification.
Partial Turnkey (Combo): You supply specialized, proprietary, or custom ICs/firmware chips, while we procure all standard passives, connectors, and bare boards.
Consigned (Kitted): You deliver all raw components and circuit boards, and XinshunPCB provides high-precision assembly, inspection, and testing services.