Assembly and Testing

Shenzhen Tontek Circuits Co., Ltd

In electronics manufacturing, assembly precision and test coverage directly determine product quality and lifespan. As a professional EMS provider, we not only offer fast and flexible PCBA prototyping and volume assembly, but also have established a complete end-to-end test system – from components to finished products – ensuring every board and every device meets your design specifications.

We support the following assembly types, with flexible line configuration based on product complexity:

· Surface Mount Technology (SMT) : High-precision placement, minimum component size 01005, supporting BGA, CSP, QFN, PoP, etc.

· Through-Hole Technology (THT) : Automatic/manual insertion for connectors, large capacitors, transformers, etc.

· Mixed Assembly : SMT and THT on the same board, suitable for power supplies, industrial control, automotive electronics, etc.

· Selective Soldering : Localized precision soldering for through-hole components, reducing thermal shock.

· Cable & Box Build Integration : Assembly of enclosures, cables, display modules, batteries, etc., delivering sub-systems or finished products.

Key capabilities:

· Flexible production lines: quick changeover between prototyping (1–100 pcs), small/medium batches (100–10K), and high volume (>10K).

· Advanced equipment: fully automatic printers, high-speed mounters, 10-zone reflow ovens, inline AOI, 3D SPI.

· Process support: stencil design, fixture fabrication, DFM analysis to help optimize your design.

We believe that assembly without adequate testing is unfinished production. Therefore, we embed testing into every critical process step.

AOI (Automated Optical Inspection) : Pre-reflow + post-reflow stations, detecting missing components, polarity, bridging, tombstoning, shift.

3D SPI (Solder Paste Inspection) : 100% measurement of solder paste volume and printing consistency, detecting printing defects early.

X-Ray Inspection : For hidden solder joints such as BGA, QFN, LGA – inspecting voiding, shorts, insufficient solder.

· ICT (In-Circuit Test) : Using bed-of-nails or flying probe testers to check opens, shorts, resistor/capacitor/inductor values, etc.

· FCT (Functional Circuit Test) : Simulating actual operating conditions based on your test plan or test board – verifying output voltage, current, communication, signals, etc.

PCBA testing

Assembled product testing

· Burn-in Testing : For power supplies, lighting, automotive products – high temperature/ambient temperature with load to screen early failures.

· RF testing

RF (Radio Frequency) testing is a critical process for evaluating the transmission and reception performance of wireless devices or modules within specified frequency ranges. Its purpose is to ensure that products operate stably, comply with regulatory standards, and coexist with other devices without harmful interference in real-world electromagnetic environments. To support our customers with overall system integration and debugging, our factory has set up a comprehensive RF test platform, including the following key equipment: 67GHz Vector Network Analyzer (VNA), Oscilloscope, Signal Generator & Spectrum Analyzer, Temperature Cycling / Thermal Chamber, With this equipment, we provide full-process support - from standalone performance verification to system-level integration - ensuring that all RF specifications are met before product delivery.

67 Ghz VNA

DC Power Supply

Oscilloscope

Signal Generator

Spectrum Analyzer

Thermal Imaging Camera

· Programming & Calibration : ISP, offline programming; calibration for sensors, power modules.

· Conformal Coating / Cleanliness Testing : Ionic contamination test, Surface Insulation Resistance (SIR).

· Environmental Reliability (optional outsourced): Thermal cycling, salt spray, vibration, drop testing.

· Standards compliance : ISO 9001, IATF 16949 (automotive), ISO 13485 (medical) certified lines.

· Traceability : Each PCBA traceable to placement batch, solder paste, reflow profile, test data.
· Statistical Process Control : Real-time monitoring of SPI, AOI, ICT yield data; automatic alerts on anomalies.

· Defect management : Isolation → analysis → 8D report → corrective action, ensuring problems do not recur.

1. Document Review : BOM, Gerber, test requirements (schematics, test points, firmware, etc.).
2. DFM/DFT Feedback : Provide suggestions for test point coverage and component placement.
3. Quotation & Samples : Provide detailed quote; produce 10–50 engineering prototypes for validation.
4. Pilot Run : 100–500 units to verify assembly and test stability.
5. Volume Release : Ship per order; provide test reports, CPK, yield data with each shipment.