Specification:
| PCBA QC | X-Ray,AOI test |
| Service | PCB,PCBA |
| Surface finishing | HASL,Lead free |
| Material raw | FR4 |
| Cu thickness | 1OZ |
| Processing | SMT |
| Line space | 8mil |
| Line width | 8mil |
Parameter
| 1 | Layer | 2 layer |
| 2 | Material | FR-4 lead free |
| 3 | Board thickness | 1.2mm |
| 4 | Finished board side | 40*20mm |
| 5 | Min.drilled hole size | 0.25mm |
| 6 | Min.line width | 0.25mm |
| 7 | Min.line spaceing | 0.25mm |
| 8 | Surface finish/treatment | HALS/HALS lead free |
| 9 | Copper thickness | 0.5-4.0oz |
| 10 | Solder mask color | green/black/white/red/blue/yellow |
| 11 | Inner packing | Vacuum packing,Plastic bag |
| 12 | Outer packing | Standard carton packing |
| 13 | Hole tolerance | PTH:±0.076,NTPH:±0.05 |
| 14 | Certificate | UL,ISO9001,ISO14001,ROHS,CQC |
| 15 | Profiling Punching | Routing,V-CUT,Beveling |
| 16 | Assembly Service | Providing OEM service to all sorts of printed circuit board assembly |
Thru-Hole Technology (THT) Assembly Process
As a traditional PCB assembly method, thru-hole mounting process is accomplished through collaboration of manual procedure and automatic procedure.
• Step 1: Components Placement - This step is achieved manually by professional engineering staff. Engineers need to quickly, yet precisely place components on corresponding positions based on client's PCB design files. Component placement must conform to regulations and operation standards of thru-hole mounting process to guarantee high quality end products. For example, they have to clarify polarity and orientation of components, to stop operating component from affecting ambient components, to make completed component placement compatible with corresponding standards and to wear anti-static wristbands when dealing with static-sensitive components like ICs.
• Step 2: Inspection & Rectification - Once component placement is completed, the board is then placed in a matching transport frame where board with components plugged in will be automatically inspected so as to determine whether components are accurately placed. If issues concerning component placement are observed, it's easy to get them rectified immediately as well. After all, this takes place prior to soldering in PCBA process.
• Step 3: Wave Soldering - Now the THT components should be accurately soldered onto circuit board. In the wave soldering system, the board moves slowly over a wave of liquid solder at high temperature, approximately 500°F. Afterwards, all leads or wires connections can be successfully obtained so that thru-hole components are firmly attached to the board.
Surface Mount Technology (SMT) Assembly Process
Compared with thru-hole mounting process, surface mounting process stands out in terms of manufacturing efficiency because it features a totally automatic mounting PCB assembly process from solder paste printing, pick and place and reflow soldering.
• Step 1: Solder Paste Printing - Solder paste is applied on the board through a solder paste printer. A template ensures that solder paste can be accurately left on correct places where components will be mounted, which is also called stencil or solder screen. Because quality of solder paste printing is directly associated with quality of soldering, PCBA manufacturers focusing on high quality products usually carry out inspections after solder paste printing through a solder paste inspector. This inspection guarantees printing has achieved regulations and standards. If defects are found on solder paste printing, printing has to be reworked or solder paste will be washed off prior to second printing.
• Step 2: Components Mounting - After coming out of solder paste printer, PCB will be auto-sent to pick-and-place machine where components or ICs will be mounted on corresponding pads in the effect of tension of solder paste. Components are mounted on PCB board through component reels in the machine. Similar to film reels, component reels carrying components rotate to provide parts to the machine, which will quickly stick parts to the board.
• Step 3: Reflow Soldering - After every component is placed, the board passes through a 23-foot-long furnace. A temperature of 500°F causes the solder paste to liquefy. Now the SMD components are bound firmly to the board.
Mixed Technology
With the development of modern science and technology, electronic products are becoming increasingly complex, driving complicated, integrated and smaller size PCB boards. It is almost impossible for PCBAs containing only one type of component taking part in.
Most boards carry Thru-hole components and SMD components, which requires collaboration of thru-hole technology and surface mount technology. Nevertheless, soldering is a complicated process that tends to be affected by too many elements. Thus, it becomes extraordinarily significant to better arrange the sequence of thru-hole tech and surface mount technology.
PCBA Professionals
Xinchenger is the premier PCB solutions provider. We can cover your PCB requirements from parts sourcing to electronic assembly. We'll help you with each step of the way and provide you with comprehensive expertise and quality assurance.
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2 Layer Board One-Stop PCB Assembly OEM Turnkey Solution PCB Manufacturing Images
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