SMT assembly service

SMT PCB Assembly Service

Fine Pitch | Fully Automatic | Built-in Detection | Made in China | Own Factory

SMT, or Surface Mount Technology, is a crucial technique for automated PCB assembly. It eliminates the manual insertion of component pins through through-holes, replacing it with the input of design files into pick-and-place machines. This automated production enhances product reliability, consistency, and facilitates rapid turnover.

The SMT PCB assembly follows a structured, chain-like process, where the bare board undergoes pick-and-place, surface mounting, and reflow soldering to form the PCBA board. In modern electronic assembly, SMT technology holds a prominent position, as the distance between components and the PCB significantly affects signal transmission. SMT assembly allows the use of leadless or short-leaded components (SMC/SMD). If your electronic project requires SMT PCBA services in China, be sure to contact FS Technology for more affordable quotes.

Top-tier SMT PCB Assembly Supplier — FS Technology

FS Technology is a Chinese PCBA supplier that offers SMT assembly services to global clients. Equipped with 7 fully automated SMT lines and state-of-the-art equipment in our factory, we facilitate all business activities from prototyping to large-scale production.

With the increasing complexity of electronics, we recognize the importance of a turnkey solution. Our engineering team collaborates with you during the design phase to help achieve circuit layouts and optimize costs according to your project requirements. Furthermore, to ensure the correctness of the final product, FS Technology implements process control throughout the assembly process, enhancing production quality and speed while safeguarding the reputation of our factory—a true win-win situation.

Production Capacity

SMT assembly line
  • Capacity: Our integrated 7 automated production lines can achieve a monthly output of 52 million placements (0.15 seconds/chip, 0.7 seconds/QFP).
  • Specifications: Accepted board sizes range from 0.25″x0.25″ to 680×500 mm, with component sizes of 0201 – 54 square millimeters (0.084 square inches). We provide a variety of options, including long connectors, 0201 packages, CSP, BGA, QFP, and more.
  • Assembly: Single-sided, double-sided, rigid, flexible, rigid-flex combination.
  • Equipment: Solder paste printer, SPI inspector, automatic solder paste printer, 10-zone reflow soldering, AOI, X-RAY, baking machine.
  • Certifications: ISO13485, ISO 9001, IATF16949, ISO 14001, ISO 45001.
  • Special Services: Design upgrades, component procurement, expedited projects, post-sales processing.
  • Industries: Medical, aviation, automotive, IoT, consumer electronics, and more.

Quality Assurance

  • More than 15 of our personnel are involved in the quality control department, effectively controlling and managing essential processes like incoming material inspection, input quality control processes, outgoing quality control processes, etc.
  • Equipped with 5 electronic engineers who are constantly putting forward constructive improvement suggestions on DFM manufacturability and the engineering process, effectively improving product quality and overall production efficiency.
  • Electronic information display boards are implemented along the production line, ensuring functional supervision of the PMC production planning process and delivery times.
  • Electrostatic bags or electrostatic protective foam (PE foam) is used for safety in packaging and to ensure the safety of the product(s) during transportation.

SMT Equipment

Juki JX-100 SMT Pick & Place Machine
Specifications6 heads with laser alignment, 14,400 components per hour small chip 8mm or less Placement points per program 2,000
Applicable Component SizesHeight: min: 0.3mm max: 6mm
Size: min: 0.75 x 0.5mm max: 33.5mm sq
Lead Pitch: 15 mil
Applicable PCB Sizemin: X 50mm x Y 30mm
max: X 330mm x Y 250mm
thickness min: 0.4mm max: 4mm
Zevatech FS-750 SMT Pick & Place Machine
Specifications3 heads with laser alignment, 8,000 components per hour small chip 8mm or less Placement points per program 2,000
Applicable Component SizesHeight: min: 0.3mm max: 6mm
Size: min: 1.0 x 0.5mm max: 23.5mm sq
Lead Pitch: 15 mil
Applicable PCB Sizemin: X 50mm x Y 30mm
max: X 330mm x Y 250mm
thickness min: 0.4mm max: 4mm
Zevatech PM-570 SMT Pick & Place Machine
SpecificationsSingle head with laser alignment, 3870 components per hour max rating Placement points per program 2,000
Applicable Component SizesHeight: max 6mm
Size: min 1.0 x 0.5mm max: 33.5 sq
Lead Pitch: 15 mil
Applicable PCB Sizemin: X 30mm x Y 30mm
max: X 406mm x Y 330mm
thickness min: 0.6mm max: 2.5mm

SMT Assembly Service Process

FS Technology has been engaged in the PCBA industry for 20 years, with a deep understanding of every step and pain point in the SMT production process. Through our services, we can efficiently and quickly fulfill your orders with high quality. Now, let us present the complete assembly process.

Preparation Phase

To ensure the quality of SMT board assembly, FS Technology meticulously reviews the files submitted by clients and inspects the purchased components before the assembly process begins. This not only avoids potential economic losses but also mitigates the risk of delivery delays. This sets FS Technology apart from other SMT contractors.

DFMA Check

DFM inspection before SMT assembly

DFMA, or ‘Design for Manufacture and Assembly,’ is a methodology that ensures the design of a circuit board enables high quality and efficiency during the manufacturing and assembly phases. Upon receiving your project files, they are promptly handed over to our engineering team. The engineers assess and review the design files for any potential deficiencies, redundancies, or other issues. If any design flaws are identified, the engineers promptly provide feedback and offer troubleshooting assistance, making successful SMT fabrication achievable.

Components Checking

After the design verification process, the project proceeds to the next stage. We procure the necessary components from our trusted suppliers based on the provided BOM file. To avoid unexpected issues during transportation that could lead to delivery delays, we employ various inspection methods to validate the quality, known as incoming inspection.

Assembling and Soldering

SMT Assembling and Soldering

Step 1: Solder Paste Application

The PCB assembly process involves the use of solder paste to secure components. The first step in surface mount assembly is applying solder paste to precise locations. This process includes spreading solder paste on a PCB stencil and then using a squeegee to allow the solder paste to drop through the holes in the stencil onto the soldering points.


Step 2: Place Components

The entire surface-mount assembly process is automated. Manufacturers are required to provide coordinate files to the equipment for efficient operation. A pick-and-place robot, equipped with vacuum nozzles, is used to select and position components based on the instructions from the coordinate files.

Step 3: SPI Inspection

This stage is dedicated to inspecting the quality of solder paste and surface-mount components. At this point, the solder paste is in a molten state, allowing for immediate adjustments if any issues are identified. Omitting SPI testing at this stage can make rework challenging, as robust solder joints have already been formed during the reflow soldering process.

Step 4: Reflow soldering

After ensuring the accurate application of solder paste and components on the board, the semi-finished SMT circuit board is transported on a conveyor belt to the reflow soldering for curing to the required specifications. At this point, the board goes through four stages: Preheating→thermal soaking→reflow→cooling. Once the entire process is completed, the molten solder paste solidifies, firmly soldering the SMD components onto the PCB. An interesting fact is that when choosing an SMT PCB manufacturer, it is advisable to examine the specifications of their reflow soldering oven, as the length and throughput can impact the quality of cooling and heating. FS Technology utilizes a 10-zone reflow oven.

Step 5: AOI

Due to the high-temperature nature of the soldering process, AOI inspection is conducted after reflow soldering to ensure the quality of the solder joints. AOI equipment uses cameras to scan the surface-mounted PCB board and compares the obtained data with set parameters. If defects are identified, they are marked for rework.


Step 1: Plug-in

For the entire PCBA project, SMT assembly is just one step, and certain components may not be suitable for this process. Therefore, through-hole assembly is required, and wave soldering is performed to complete the PCBA board.

Step 2: Cleaning

The process involves the use of various chemical agents such as solder, flux, etc. If the PCB is not cleaned after assembly, it may shorten its lifespan. FS Technology will clean the PCB with isopropyl alcohol.

Step 3: Final Test

The final stage of the PCB assembly process is conducting functional tests to verify that the PCB operates as expected. Additionally, depending on the application, there may be further requirements. For instance, automotive PCB might undergo drop tests, and medical PCB might require halogen testing.

Trends in SMT Electronic Assembly

The trends in electronic manufacturing are constantly evolving, and as a leading SMT assembly factory in China, FS Technology has been closely monitoring these changes and preparing for them.

Why Surface Mount PCB Assembly?

advantages of surface mount technology

Currently, the proportion of SMT in electronic boards far exceeds that of THT, and one major reason is that SMT assembly is more conducive to automation. In contrast, THT may still require manual intervention, especially when dealing with large components. The benefits of machine production include tireless and error-avoidant work compared to the potential errors in manual assembly.

Secondly, the geometric dimensions and volume of SMD components are much smaller than DIP components, weighing only a tenth of DIP components. This advantage allows SMT PCBA to fit more tightly, enabling effective space utilization.

In terms of circuit performance, SMT technology directly solders components to the surface of the PCB without the need for leads to pass through holes, thereby reducing the distance between components and the PCB. This not only improves the performance of signal transmission, but also significantly reduces electrical and thermal noise in PCB.

Future of Surface Mount Technology

As of 2023, the market size of SMT assembly services has reached $6 billion and is expected to continue growing. By 2035, it is anticipated to surpass $15 billion, with a compound annual growth rate of 7%. This robust development trend is attributed to automation, miniaturization, and cost-effectiveness.

In the future, miniaturization will continue to reduce the spacing between component leads, possibly going below 0.010 inches. Faced with this change, SMT service providers should further optimize soldering techniques to prevent tiny solder pads from being threatened by heat.

Additionally, environmental issues are a significant concern. The RoHS directive explicitly states that the use of lead solder in assembly can be harmful to the environment. Manufacturers should adopt lead-free PCB assembly as an alternative to continue serving the electronics industry.


If you’re struggling to choose the right SMT assembly service factory for your project, why not contact FS Technology? We are always dedicated to PCB assembly services and offer high-quality services at a lower cost for you.

Absolutely! With over 20 years of experience in the PCBA industry, FS Technology has consistently provided high-quality services and established itself as a trusted name in the Chinese PCBA industry. If you are learning about us for the first time, consider checking out our customer reviews!

Unlike other manufacturers, FS Technology prioritizes service and quality. We do not recommend obtaining PCBA directly through online quotes. Instead, we tailor service projects for our clients after receiving their emails. This approach strengthens our mutual understanding and helps reduce your project costs. If you need an SMT manufacturing quote, simply contact us via email – it’s that simple!

You’ve come to FS Technology, so why not consider trusting us?


If you really don’t need us, you can choose a more suitable SMT PCB assembly supplier based on the following recommendations:

  • Compare prices – this goes without saying, the key is to ensure a balance between price and quality, don’t sacrifice one for the other!
  • Check if the manufacturer uses advanced equipment – this helps understand the company’s investment in production, reflecting its strength.
  • Understand the manufacturer’s production capacity to avoid losses due to production delays caused by limited capacity.
  • Advanced Reading: How to find the right PCB assembly company?

The global manufacturing industry is shifting towards China, and if you need offshore manufacturing, China is a good direction to consider. China SMT assembly services attract customers with a match of quality and price. It is believed that most companies can meet your requirements and consistently adhere to international certification standards!

If your business excels in marketing, then Turnkey PCBA solutions will be your best option. You can focus solely on your strengths, and as for other tasks, FS Technology will take care of everything for you. For projects that prioritize cost, it is recommended to use a semi-turnkey approach!

Automation is the future mainstream trend, aiding in mass production and avoiding human errors. Therefore, FS Technology is increasing its investment in equipment, committed to building a digitally intelligent factory to achieve the automation of SMT circuit board assembly.

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