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Xinxintian Industrial Zone, Shajing Street,Bao'an District, Shenzhen, China

An guide for hybrid proce from SMT
Assembly Technology: An guide for hybrid processes from SMT
Abstract :PCB assembly technology is undergoing revolutionary changes, with the development of electronic products towards the essence, small and high density. The article depths the main processes of Surface Mount Technology (SMT), Through-Holl Technology (THT) and hybrid assembly processes, and adds ISO 9001 and ISO 13485 and 6110G to reveal 9 major stages and 4 quality control strategies of PCBA production. By introducing the intelligent supply chain management practices of the ConsumerPCBA, it provides electronic manufacturing companies with a full-cycle solution from design adaptation to large production, which helps improve the increase in production efficiency and product yield by more than 30%
I. Development of PCB assembly technology and Key process
1. Surface Mount Technology (SMT): Benchmark for accurate construction
• SMT process perfectly achieves high-collective placements of micro components (01005 size) through automated equipment. Its main benefits include:
• Micron-Level Positioning: Placement accuracy using a visual alignment system reaches ± 25μm
• Lead-free tolling: ROHS-Compliant SN96.5/Ag3.0/Cu0.5 Solder Paste, Malting point 217 ℃
• skills production Saritical capacity of plassemth mispainch
Process flow diagram:

2. Holl Technology (THT): A reliability-first choice
1.The THT technique is suitable for high-power devices and connectors, and its characteristics include:
• Heat dissipation advantage: Suitable for heat dissipation devices such as TO-220 package, and the thermal resistance is reduced by 15%
• Process compatibility: Selective wave soldering technology realizes local welding and reduces energy consumption by 30%
3. Hybrid PCB Assembly : the ultimate solution for complex PCB design
In the field of 5G base stations and automotive electronics, hybrid assembly achieves performance leap through a three-order optimization strategy:
Layout planning: SMD and THT partition design, spacing ≥ 2.5mm to prevent thermal interference Soldering sequence: reflow soldering first and then wave soldering to avoid secondary high temperature damage Detection coordination: X-ray + BGA rework station solves the problem of hidden solder joints
II.PCBA full process analysis and quality control
1. 9 core process steps (based on IPC-J-STD-001 standard)
Steps | Key technical parameters | Quality control points |
---|---|---|
Bare board baking | 125℃/4h, humidity <5%RH | Eliminate substrate stress and prevent board explosion |
Solder paste printing | Steel mesh thickness 0.1-0.15mm | SPI detection coverage ≥98% |
Component placement | 0402 component accuracy ±0.03mm | Nozzle pressure 0.5-1.2N adjustable |
Reflow soldering | Peak temperature 245±5℃, time 60-90s | Real-time monitoring of 100 temperature measurement points |
AOI detection | Defect recognition rate ≥99.7% | Deep learning algorithm false alarm rate <0.3% |
Wave soldering | Solder wave height 8-12mm | Nitrogen protection oxygen content <100ppm |
Cleaning process | Aqueous cleaning agent pH value 6.5-7.5 | Ion contamination <1.56μg/cm² |
Functional test | Flying probe test speed 200 points/second | Test coverage 100% |
Conformal coating | Coating thickness 20-50μm | Salt spray test ≥500h without corrosion |
Key process breakthrough: In the field of automotive electronics, vacuum reflow technology can eliminate BGA bubbles and reduce the void rate from 5% to below 0.5%.

III. Document standardization and smart manufacturing exercise
1. Design document requirements (IPC-2581 standard)
• Gerber File: 32 signal layers + 16 power layer definitions include
• ODB ++: Integrates the bill of content and 3D model data, DFM inspection pass rate has increased by 40%
• Assembly drawing specification: component polar identity error <0.5 mm, fullproof design coverage 100%
2. Consumption PCBA’s smart production system
Create competitive advantage through four new technologies:
- Digital Twin: Virtual debugging reduced the new product introduction cycle from 30%
- Material Smart Cloud Warehouse: 100,000+ SKU Real-Time Inventory, Shortage Warning Response Time <2H
- AI quality prediction: Depending on a million-level defect database, yield prediction accuracy reaches 95%
- Green Manufacturing: Lead-free process + waste water recycling system, carbon emissions reduced by 45%
Customer case: A medical equipment manufacturer gained 60% increase in increasing density through mixed assembly adaptation, and its products passed the IEC 60601–1 medical certification.
IIII. 7 Criterics to select 7 High Quality PCBA suppliers
- Certification System: ISO 9001+ IPC -A -610 Class 3 Dual Certification
- Process capacity: 0.3 mm pitch CSP packaging and support 20-layer HDI board
- Delivery Guarantee: 48-hour fast prototype, batch order on-time 99%
- Component Control: Original authorized agent + X-ray detecting authenticity
- Testing capacity: with a full set of ICT, FCT, environmental stress screening equipment
- Technical Assistance: DFM analysis team has an average experience of over 8 years
- Cost Adaptation: BOM Cost Analysis System helps customers to reduce the cost of 15%-30%
Summary and approach
The PCB assembly technology is developing towards intelligence (industry 4.0), high density (embedded components), and green (bio-based mix). Covenant helps customers to achieve the following by constructing a full-link digital platform of “design-testing”:
• First pass rate (FPY) increased from 85% to 98%
• New product growth cycle reduced by 40%
• Large scale production costs reduced by 25%