PCB Assembly Manufacturing Process - JLCPCB Factory Tour

One of the most important factors to create a working circuit board is the assembly technique and process, such step has to be controlled and carefully executed to ensure the wellness of the final produced device.

JLCPCB provides PCB Assembly by taking in charge the full steps of soldering each component to its placement on the board based on their capabilities which shorten the path for engineers and companies by saving more time for them.

The PCB Assembly process comes directly after the PCB manufacturing and by sweeping away the necessary amount of solder paste on the components exposed pads then placing the components for the next step which is the Reflow to accomplish the circuit assembly.

PCB Assembly at JLCPCB

The JLCPCB PCB Assembly service is a reliable yet efficient option for customers to satisfy their electronics manufacturing needs, by offering a high-quality assembly for a judicious price, such PCBA service is at the top of the list for every engineer’s choice.

The more assembly insurance leads to more effectiveness of circuit boards, that’s the main reason behind the PCB Assembly success around JLCPCB PCBA service, where every manufacturing step is thoroughly treated by knowledgeable and qualified staff.

1- Parts preparation

As soon as the customer upload the PCB design files, the JLCPCB engineers arrange the related “data for manufacturing” and release the electronics components needed quantities for assembly by preparing the parts to be loaded later to the assembly pick and place machine feeders. The assembly includes all the parts available in the JLCPCB parts library which covers the Surface Mounted Devices and the Through-Hole components as well, the customers could select their parts through this library where they can search the needed components through the very well-arranged parts categories that sort more than 350K components. The parts are recognized automatically through the Assembly system based on the customer’s provided “Bill Of Materials” file that has all the needed information for each part like the part Prefix and quantity, all the needed parts are prepared and wait for the PCB manufacturing step.

2- Solder Paste Application

The faster we go the faster we deliver, not only the parts should be prepared while the PCB manufacturing but also the Stencil preparation as well, this is another step executed in parallel to the parts preparation and PCB manufacturing. Stencil is the key to drop the exact needed solder paste amount on each component’s pad.

JLCPCB uses a fully automated process for solder paste deposit and inspection, as soon as the PCB gets ready out of the PCB manufacturing process it is then directly transferred to receive the solder paste through the exposed pads on top of the Stencil.

The applied Solder paste cover then the spots of the exposed pads after getting the solder paste sweeped on the Stencil.

3- Solder Paste Inspection (SPI)

Because every step has to be carefully supervised then the solder paste application is checked through the SPI process that evaluates the quality of the solder paste deposit on the PCBs to ensure that all the components pads received the necessary solder paste to properly achieve the components attach to the PCB and to maintain a durable , this is a very important inspection step since it prevents miss assembly of the components which could cause the miss functioning of the board therefor the solder paste inspection helps to disclose any potential faults at an early stage of the Assembly process.

JLCPCB uses a fully automated machines for the inspection through its Automated Optical Inspection (AOI) and its advanced X-Ray high-definition cameras that determines the solder paste geometry on the pads and decide the Good and Bad execution of the SPI by comparing the captured real-time camera images to the ideal solder paste deposit reference image created by our engineers.

This inspection will certainly help to create a successfully assembled circuit board equipped by properly connected components with a durable electrical connection.

4- Components Pick and Place

After getting the solder paste applied to the relevant area of the PCB then it goes to receive the components, this step is so delicate and has to be performed by some sophisticated machines called the Pick and Place machines or P&P machines, this machine as the name indicates, it pick up the components and place them on the PCB, sounds like an easy task but this is very complicated step since the handling of the components by the machine has to be so fast in order to successfully complete the parts placing within the shortest possible time.

The machine is first loaded with components through its many feeders that could receive parts reels, tubes or even waffle pack then the heads of the machine arm move to take the parts and lay them on the PCB, those heads could take parts of several packages (small and big parts).

The machine knows where to positionate the arm to exactly match the correct part position on the board, these moves are performed through a program that defines the X and Y center position of the components, this program is manually created by JLCPCB engineers based on the “Pick and Place” file provided by the customer.

5- Reflow Soldering

Probably this is the most widely commonly used process for all PCB manufacturers to attach surface mounted components to circuit boards, the key to achieve this step successfully is the also the used equipment.

JLCPCB uses the appropriate reflow soldering machine equipped by suitable Oven capable to assemble several boards sizes and helps to achieve the required line speed.

The form factor for a well assembled part is surely the assembly process itself, even with the suitable machine there are some other requirements to follow in order to properly solder the components, the main target is to create solder joints by pre-heating the components/PCB and solder paste then melting the solder through acceptable reflow profile that prevents causing any damage by overheating.

6- Assembly Inspection

This is another assembly insurance, after getting the components soldered to the PCB we must check that all the parts have been properly attached and there are no errors of misalignment or cold joints, or even short circuits of the assembled pads, for this inspection the Optical camera is needed to determine the Good and Bad parts, the part assembly status judgment is also decided compared to an ideal image reference uploaded by JLCPCB engineers.

In some specific cases where the camera could not spot the pads then the X-Ray inspection machine is used to check the assembly especially for components where the pads are hidden underneath the component’s hood (for BGA package)

After getting the boards very well assembled and fully inspected and tested, those produced circuit boards are then cleaned and delivered to JLCPCB customers. Overall, the assembly seems to be easy from the outside of the process, but from the inside there are many delicate steps to perform in order to successfully achieve a durable working circuit board for a reliable price.

Making tech innovation easier is what JLCPCB always pursues. JLCPCB is able to provide the best price with high-quality products due to the full implementation of intelligence management system, use of state-of-the-art equipment, and large-scale effect on manufacturing. In order to make budget no longer an obstacle for electronic engineers and makers. Right now JLCPCB is offering $60 new user coupons. Sign up on JLCPCB official website and unlock your creativity with us!