One-stop SMT assembly

Our factories provide high -quality SMT assembly services for medical, aerospace, national defense, industry, automobiles, communications and consumer electronics.

Surface Mount Technology (SMT) is a technology that put electronic components directly on the PCB surface. This technology uses automated equipment to accurately place the tiny electronic components on the PCB pad, and complete the assembly of the circuit board through the process of backwalm or peak welding. SMT technology has high degree of automation and accuracy, can effectively improve production efficiency and reduce human errors, so it has been widely used in modern electronics manufacturing.

We are equipped with the state-of-the-art manufacturing facility and sophisticated machinery to support the fabrication. We also have highly trained and experienced personnel to make sure your job is done faster with high quality. Our capabilities in high quality SMT pcb assembly services include, but not limited to:

●Cutting-edge prototype SMT assembly line ensuring fast and flexible production.
●Vast inventory of production- ready components for ensuring faster production.
●Advanced machines providing unrivalled technical capability and product quality.
●BGA removal and replacement station, SMT IR rework station, and thru-hole rework station.
●Clean, well-organised and secure environment for the final assembly.
●Inspection and testing using X-ray analysis, AOI, Microscope to 20X.

Why choose LST

Strict quality system

LST has set up the quality management system certified RoHS, IPC-600, IPC-610, ISO, IATF, and REACH for PTH and SMT PCB assembly.

Fast delivery

We have 8 high-speed SMT mating lines，Daily production capacity exceeds 30 million points.We can quickly complete the customer’s order.

Competitive Prices

In-house manufacturing enables us to control the quality and costs as well. In addition, we have reliable suppliers who offer qualified materials at lower prices.

Thoughtful service

24-hour rapid response to provide you with one-on-one nanny consultant pre-sales, sales, after-sales tracking service, for you to answer any difficult questions.

SMT assembly step

An SMT assembly line is automatic, including a loader, solder paste printing machine, SPI (solder paste inspection) machine, high-speed and functional mounting machines with feeders, reflow oven, and AOI (automatic optical inspection).

The SMT PCB assembly process is:

Step 1. Solder paste printing. A loader sends a PCB into the solder paste printing machine, where an SMT stencil is set up. A scraper presses the solder paste to pass the holes of the SMT stencil and print on the PCB pads.

Step 2. SPI. The PCB printed with solder paste passes the SPI machine, which quickly scans the solder paste and compares the thickness, position, and size of the solder paste with the set-up parameters. It ensures solderability.

Step 3. Placing SMDs. The PCB with solder paste goes into a mounting machine, where a feeder sends SMDs to a position, and the nozzles of the mounter move to pick and place the SMD to a designated PCB pad one by one. The high-speed mounter picks and places SMDs with small footprints, such as resistors and inductors, while the functional mounter picks and places SMDs with larger footprints, such as connectors and ICs.

Step 4. Reflow soldering. The PCBA enters a reflow oven, where it is preheated and baked. The reflow temperatures change according to the reflow profile. The solder paste melts to release the flux, which activates to facilitate the soldering. At the peak of reflow soldering, the PCB pads, solder paste, and SMD pins form metallic compounds, which marks the success of soldering. After that, the temperature goes down. The PCBA cools down and forms permanent joints.

Step 5. AOI. The PCBA passes the AOI machine, which scans the entire surfaces of the PCBA and compares it with the reference. The AOI ensures almost all surface defects are identified and rectified, including soder bridges, voids, tombstones, etc.

Our Capabilities

SMT Program	Process Capabilities
Layers	1-42 layers
PCB Size	Lw:5050–510mm*460mm
PCB Thickness	0.3MM-4MM
PCB Material	Flex/Rigid/Composite/Aluminum Substrate
Component Size	01005(Inch)–45mm*100mm
Component Pitch	IC minimum pitch 0.25mm/BGA minimum pitch 0.25mm
Component Height	Maximum 20mm
Patch Precision	chip:±0.03mm IC:±0.025mm
Maximum Daily Capacity	9.07 million points/11 hours
Printing Machine	ZS-A5, ZS-ASE,GKG-G5, Printing accuracy:±0.025MM
Mounter	JUKI:±0.035MM YAMAHA: ±0.025MM
AOI	VCTA-D810, VCTA-D850 Online Dual Rail AOI
SPI	VCTA-V850E,3D-SPI In-Line 3D SPI
X-ray Inspection	UNICOMP– AX8200 tester for BGA type chips
First Article Tester	Model: HX-FAI-300 high-precision first piece detector

SMT Cases at LST

Medical board SMT

Solar Controller PCB

Smart home products

IoT products pcb

The future of SMT technology

SMT technology will continue to maintain its important position in the future and show multiple development trends.

1. With the continuous improvement of the miniaturization and integration of electronic products, SMT technology will further develop to meet the demand for smaller and more powerful components.

2. Intelligence will become an important development direction of SMT technology in the future. SMT technology will apply artificial intelligence and machine learning technology more to achieve automated production.

3. The improvement of environmental awareness will promote the use of more environmentally friendly production methods. The SMT industry adopts surface assembly to reduce lead pollution and harmful waste in traditional welding processes, which is more in line with environmental protection requirements.

4. The continuous development of intelligent manufacturing technology, the SMT industry will gradually realize digitization and intelligence. This will help improve production efficiency, reduce costs, and improve product quality, thereby enhancing the competitiveness of enterprises.

The best SMT PCB manufacturer-LST

1.LST has a strong engineering team and professional component procurement team. We are equipped with innovative technologies and advanced production equipment (tin paste printing machine, pickup machine, reflux furnace, AOI detector).

2.LST provides all -round services, including services before -sale, medium and after -sales. Our high -quality capabilities and service attitude can provide solutions as soon as possible when the customer needs. We actively solve each after -sales quality problem during the after -sales stage.

3. We have passed the UL ISO9001, Rohs/Reach and other certifications, which reflects our production qualification.

4.LST has 18 years of manufacturing experience and has won a good reputation in the industry. We provide one -stop PCB business for customers around the world.