PCB Assembly

Printed circuit board assembly services

Publish Date:2020-11-06

It has its own high-precision SMT Mounter, silk screen printing machine, and automatic board feeder. It can provide SMT chip printed circuit board assembly services for small package 0201 components. SMT production line is equipped with 5 high-speed chip assembly lines, 5 dip plug-in assembly lines, AOI automatic optical detector, automatic solder paste printing machine, lead-free wave soldering, 8 temperature zone reflow soldering, ICT tester, aging, cleaning tools, etc.

Printed circuit board assembly services

Layers: 2-40
Plate thickness: 0.2-7.0mm
Large copper thickness: 2oz
The large size of the finished product: 650 * 1100mm
Small line width / spacing: 3 / 3mil
Thickness and aperture ratio of large plate: 12:1
Small mechanical drilling hole diameter: 6mil
Distance from hole to conductor: 3.5mil
Impedance tolerance (Ω): ± 5% (< 50) ± 10% (≥ 50)
Surface treatment process: lead-free tin spraying, OSP, chemical precipitation of gold, chemical nickel, palladium, silver precipitation, tin deposition, hard gold plating, soft gold plating, gold finger, etc.
Materials: FR-4, high Tg, halogen-free, high frequency (Rogers, Isola…), CEM, etc
Circuit board assembly process
1. According to customer Gerber file and BOM, make SMT production process file and generate SMT coordinate file
2. Check whether all production materials are ready, make a complete set of orders, and confirm the PMC plan of production
3. Carry out SMT programming, and make the first board for checking to ensure that there is no error
4. According to the SMT process, laser steel mesh is made
5. Solder paste printing to ensure that the solder paste after printing is uniform, with good thickness and consistency
6. Mount the components to the circuit board through SMT Mounter, and carry out AOI automatic optical detection when necessary
7. Set the perfect reflow furnace temperature curve, let the circuit board flow through the reflow soldering, solder paste from paste, liquid to solid, after cooling can achieve good soldering
8. Through necessary IPQC intermediate inspection
9. Dip plug-in process passes plug-in materials through the circuit board and then flows through wave soldering for welding
10. Necessary post furnace process, such as leg cutting, post welding, plate surface cleaning, etc
11. QA conducts a comprehensive inspection to ensure the quality is OK。

Printed circuit board assembly services

PCBA test

PCBA testing is a key quality control link in the whole PCBA processing process. It is necessary to strictly follow the PCBA test standards and test the circuit board’s test points according to the customer’s test plan.

PCBA test also includes five main forms: ICT test, FCT test, aging test, fatigue test, and test in a harsh environment.

ICT (in-circuit test) test mainly includes on-off, voltage and current value and fluctuation curve, amplitude, noise, etc.;

The FCT (functional circuit test) test needs to burn the IC program, simulate the function of the whole PCBA board, find the problems in the hardware and software, and equip the necessary production fixture and test stand;

The burn-in test is mainly to power on PCBA board and electronic products for a long time, keep them working, and observe any failure faults. The electronic products after the aging test can be sold in batches;

Fatigue test is mainly to sample PCBA board and conduct high-frequency and long-time operation of functions to observe whether there is a failure, such as continuously clicking the mouse for 100000 times or turning on and off the LED light for 10000 times to test the failure probability, to feedback the working performance of PCBA board in electronic products;

The test under severe conditions mainly exposes the PCBA board to the temperature, humidity, drop, splash, and vibration of the limit value to obtain the test results of random samples to infer the reliability of the whole batch of PCBA plates.

Shenzhen IDEASPCB Technology Co., Ltd. provides overall PCBA OEM processing services, including upstream electronic components procurement to PCB production and processing, SMT chip, dip plug-in, PCBA testing, finished product assembly other printed circuit board assembly services. The company gives full play to its competitive advantages in scale procurement and quality control, and signs long-term cooperation agreements with many domestic and global electronic component manufacturers to ensure the quality of raw materials and stable supply, and transfer the preferential treatment to customers. Long term maintenance of IC, resistor, capacitor, inductor, transistor, and other procurement advantages can greatly save customer inventory costs, improve production turnover efficiency, and save time. We provide PCBA processing services for customers in the USA, UK, Korea, Russia, France, Canada, Australia, Romania, and Switzerland.

We provide PCBA processing services, focusing on the quality of circuit boards and PCBA quality control system. In the packaging process of components, high-quality solder paste, automatic printing machine, high-speed mounter, upper and lower eight temperature zone reflow soldering, AOI automatic optical detector, and ICT tester can effectively ensure the reliability and quality of electronic packaging process. Also, perfect IPC, IPQC, OQA, other management processes, clear job responsibilities, and strict IPC electronic assembly acceptance standards.

For the quotation of printed circuit board assembly services:

1. Complete PCB board making document (Gerber file) and board making requirements;

2. Complete BOM (including model, description, etc.);

3. PCBA assembly drawing.

PS: report PCBA function test cost, and provide PCBA function test method.

Printed circuit board assembly services

The manufacturing process of printed circuit board assembly involves a series of processes, such as PCB manufacturing, PCBA component procurement, inspection, SMT chip processing, plugin processing, program firing, testing, aging, etc. The supply chain and manufacturing chain are long, and the defects in any link will lead to the poor quality of PCBA board in large quantities, resulting in serious consequences.
In that case, the quality control of printed circuit board assembly processing is essential in electronic processing. What is the main quality control of PCBA processing? The following is a summary of professional PCB assembly factory idea PCB

Printed circuit board assembly services
  1. First of all, process analysis is carried out for Gerber files of PCB, and manufacturability report (DFM) is submitted for different customer requirements. Many small manufacturers ignore this but tend to this. It is easy to produce bad quality problems caused by poor PCB design and a lot of rework and repair work.
  2. Procurement and inspection of PCBA components
    It is necessary to strictly control the procurement channels of components and purchase from large traders and original manufacturers to avoid second-hand materials and counterfeit materials. It is also necessary to set up a special PCBA incoming inspection post to strictly inspect the following items to ensure that the parts are free from faults.
    PCB: check reflow oven temperature test, no flywire through-hole is blocked or ink leakage, the board surface is bent, etc.
    IC: check whether the screen printing and BOM are identical, and keep them in constant temperature and humidity.
    Other commonly used materials: check screen printing, appearance, power measurement, etc.
  3. SMT assembly
    Solder paste printing and reflow furnace temperature control system are the key points of assembly, which need to use laser steel mesh with higher quality requirements and better processing requirements. According to PCB requirements, some need to increase or reduce the steel mesh, or U-shaped hole, make the steel mesh according to the process requirements. The reflux furnace’s temperature control is significant for the wetting of solder paste and the firm welding of steel mesh, which can adjust according to the normal SOP operation guide.
    Also, strict implementation of AOI testing can greatly reduce the adverse effects caused by human factors.
  4. Plugin processing
    In the process of the plugin, the mold design for the wave soldering is the key. Using the mold to improve the yield is a process that PE engineers must continue to practice and summarize.
  5. PCBA processing board test
    For orders with printed circuit board assembly test requirements, the main test contents include ICT (circuit test), FCT (function test), burn test (aging test), temperature and humidity test, drop test, etc
    Precautions for processing printed circuit board assembly
    SMT is one of the basic components of electronic components, which is called the external assembly technique. It is divided into no pin or short lead. It is a circuit assembly technique by reflow soldering or immersion soldering. It is also a technique in today’s electronic assembly industry. SMT technology is used to mount smaller and lighter components so that the circuit board can complete great detail and miniaturization requirements. This also requires higher SMT processing skills. Therefore, in operating and adding SMT components, there are many things to be observed and noticed.
    1、 SMT solder paste processing need to pay attention to the following things:
  6. Constant temperature: it is suggested that the refrigerator’s storage temperature should be 5 ℃ – 10 ℃, not lower than 0 ℃.
  7. Out of the warehouse: must abide by the first out principle, do not form solder paste in the freezer storage time is too long.
  8. Freezing: take out the solder paste from the freezer and freeze it naturally for up to 4 hours. Do not close the bottle cap when freezing.
  9. Situation: it is suggested that the workshop temperature should be 25 ± 2 ℃ and the relative humidity should be 45% – 65% RH.
  10. Used solder paste: it is recommended to use up the solder paste after opening the lid within 12 hours. If you need to keep it, please fill it in a clean empty bottle, seal it, and put it back in the freezer.
  11. Paste amount on the steel wire: the amount of paste placed on the steel wire at a time should not exceed 1 / 2 of the height of the scraper when printing, to observe frequently, add frequency and add less.
    2、 SMT chip processing and printing homework need to pay attention to:
  12. Scraper: the scraper is made of steel scraper, which is conducive to the forming and stripping of solder paste printed on a pad.
    Scraper angle: 45-60 degrees for manual printing; 60 degrees for mechanical printing.
    Printing speed: manual 30-45mm / min; printing press 40mm-80mm / min.
    Printing condition: temperature is 23 ± 3 ℃, relative humidity is 45% – 65% RH.
  13. Steel mesh: the thickness of steel mesh and the shape and proportion of opening are selected according to the products’ requirements.
    QFP / chip: chips with spacing less than 0.5mm and 0402 need laser drilling.
    Detection of steel mesh: What should stop the tension test of steel mesh once a week, and the tension value should be more than 35n / cm.
    Clean the steel mesh: when printing 5-10 PCBs continuously, wipe it with dust-free screen paper once. What should not use rags?
  14. Cleaner: IPA
    Solvent: clean steel mesh when using IPA and alcohol solvent, can not use chlorine-containing solvent because it will damage the composition of solder paste, affect all morality.
    In a word, printed circuit board assembly realizes different functions by adding various electronic components such as capacitors and resistors on the PCB board. If What can firmly install these components on the PCB, they need various SMT chip processing technologies for processing and assembly.
    SMT chip processing is a kind of circuit assembly technology. SMC or SMD, short for pin free or short lead, is installed on the surface of the printed circuit board or other substrate and is welded and assembled by reflow soldering or immersion soldering.
    The SMT process’s basic elements are solder paste printing, part mounting, reflow soldering, AOI optical inspection, maintenance, and plate splitting.
    SMT chip processing advantages: to achieve the electronic product assembly degree, high reliability, miniaturization, low cost, and production automation.