?Publié le 2020-03-23
Un guide simple pour un assemblage parfait de circuits imprimés
Fond d'assemblage de PCB
A printed circuit board or PCB is a significant part of all the electronic devices. The process of electronic revolution started with the manufacture of PCB in the 1930s by Paul Eisler. Soon after its invention, PCB became the most wanted part of everyday devices which include computers, TVs, Air conditioners, fridge, medical devices and so on. And now pcb assembly manufacturer has become a key figure in developing modern printed circuit boards.
How does pcb assembly manufacturer place components?
After manufacturing a printed board, it comes to placing the components on it by different techniques. This is called the PCB assembly. You should know that it is the most important and decisive phase when we place the required components on the circuit board to determine its sort of functionality.
This article will tell you about the pros and cons of fabricant d'assemblage de circuits imprimés or electronic assembly, the difficulties in the procedure, the methods adopted to successfully do it, the precautionary measures and the advantages of the assembly in turn. How intriguing and fascinated is to observe the large number of PCB to be manufactured and then assembled in today’s industrially revolutionized age? How numerous components are assembled onto the circuit boards in very little time? All these questions and queries have reasonable answers in this blog post.
Hurdles in PCB Assembly
Many hurdles and issues emerge in the way for the persons who are so good at PCB manufacturing and assembly but they want to develop their PCB design. The purpose of this article is to help those seekers so that they can easily understand the mostly done mistakes and misleads in the process. In this way, they can prevent the loss of too much time as well as cost. So, keenly ponder on these issues that may block your way to the successful assembly. Similarly, pcb assembly manufacturer can also get help from it.
Defective Design in pcb assembly manufacturing
The problem that often arises is that the design is not much under the PCB structure itself. The reason is that while making a design, the PCB assembly is not into account. Instead, they altogether focus on the board itself. In this way, the design is not suitable for that board that will cause functioning problems later on.
Components’ inappropriate Placement
The second big problem pcb assembly manufacturer face in PCB assembly is the wrong or inappropriate location of different components. If the components are located too close to each other, the board will not function properly and will cause serious malfunctioning in the running process. On the other hand, mostly you can place the components unevenly on the board that will also cause misfunctioning afterward.
Component Availability in pcb assembly
The major reason for the product delay is the unavailability of the component being used in the assembly of that board. Many a time, the vendor is unable to find the respective component for the assembly and thus the whole process is blocked and delayed.
Mixing of Technologies
The mixing of technologies causes the loss cost as well as the time. And fabricant d'assemblage de circuits imprimés have to revise all the process from the start. If you are using through-hole technology, then you should avoid surface mount technology and use the earlier one in the whole board assembly. Mixing them both will cause confusion and cost enhancement and time taking too.
Improper Package Size
Pcb assembly manufacturer should follow the design and the circuit board size. The designer should select the size of the components being used in the assembly. If the size of the components is too large that they can’t be placed all on the board then, the assembly will not finish with success. In the same way, if the components are too small that there is much space on the circuit board, it will cause the extra weight of the PCB.
Pcb assembly manufacturer Absence Of Markings
It is advisable to mark the positions of the components on the board before their placement. If we place them wrong on the circuit board, then there will be all waste of time and the devotion. In the end, we will get no product of our interest.
The most critical process before importing is to inspect the footprint and programming of the circuit board for the customer’s needed facility. If something placed defective is left on the board and is not inspected before loading to the market, it will destroy the credibility of your product and the purpose of your whole service will be buried in just a few moments.
Technologies for PCB Assembly
In PCB assembly, two technologies are a big deal. These are through-hole technology and surface mount technology. pcb assembly manufacturer use it mostly.
Plated Holes Technology
In this technology, the components attached to the circuit board by drilling holes in the board. This is the most convenient method because it shows maximum effectiveness.
Surface Mount Technology
In this technology, the components get attached to the outer surface of the circuit boards by different feasible methods. This technology is faster than the hole technology and uses different types of machinery to work efficiently.
- Equipment Required for fabricant d'assemblage de circuits imprimés
The particular equipment that is requisite in the process of PCB assembly is:
Solder Paste Printing Machine
Solder Paste Inspection Machine
Glue Dispensing Machine
Pick and Place Machine
Reflow Soldering Machine
Wave Soldering Machine
Automatic Optical Inspection Machine
In-Circuit Test Fixture
Functional Validation Test Fixture
- processus d'assemblage du circuit imprimé
pcb assembly manufacturer carry four important steps. These are:
The first step in PCB assembly is the use of solder paste onto the maneuvered circuit board. A Solder is a mixture that has the particles of metal alloys. It acts as an attaching force to hold the fabricated circuit board together. A steel stencil acts as a binder before using the solder paste. The solder paste passes through the cuts and gaps of the stensil and makes the contact points settle and sit completely and permanently on the circuit board. This all is done by a solder paste printing machine.
Automated Component Placement-Pcb assembly manufacturer
Il s'agit de la deuxième étape de l'assemblage du PCB et c'est la partie la plus critique et cruciale de l'assemblage. Avant le placement des composants, une machine de distribution de pâte est utilisée pour appliquer des touches de pâte sur la carte PCB. Ceci est appliqué dans les zones où les composants vont se fixer, pour les aider à se fixer à long terme.
Now start the most important phase. The pick and place machine lift the parts and places them onto the exposed part onto the circuit board. As this part of the procedure is very critical and considerate, fabricant d'assemblage de circuits imprimés should finish this step by hand, in which special tweezers place the segments properly on the board. The pick and place machines can accurately locate the correct positions for the components. The speed of the machines is so faster than up to 30,000 parts can be attached to the circuit board in just an hour.
Soldering- Important technique of pcb assembly manufacturer
Soldering accounts for Reflow soldering and Wave soldering. But the former is the most widely used soldering technique. When pcb assembly manufacturer attach all the parts to the circuit board, they are translocated along with transport by using a special tool called Reflow soldering machine. The PCB layers tolerate different zones having different harsh temperatures.
The function of this step is to dissolve the paste and then again solidify to the electrical contact points between the components and the particularly isolated pads. Wave soldering utilized the technique of welding the components onto the circuit board. The PCBs are preheated to avoid the stun. Then a paste wave is made up inside a tank in such a way that the underside of the sheet gets the segments welded to it by the bound wave produced in the tank.
Inspection is very important step for fabricant d'assemblage de circuits imprimés. Then why not check the PCB after its assemblage. Testing and review are the most important part of the assembly. It saves the repeating of process and time too. The automated inspection method is used for this purpose. Another important test is the in-circuit test. Here, we use a stack of pins.
Each fabricated board is placed on these pins and moved downward. Any crack or abnormality in the circuit can be predetermined and hence can be improved. A function validation test is also a very significant test that checks the best programming of the PCB to give quality and better information to the customers.
5. Powerful Tricks For pcb assembly manufacturer
If you want to become a master at PCB assembly, then you are in the right place. I will tell you the steps which you have to consider with great care. Follow these steps and you will meet with a successful PCB design.
Check Footprint’s Feasibility
The success of the PCB design is in matching it with the footprint. The best way is to draw the design on the paper and then overlay the components.
Use component Substituents
As we have discussed that the unavailability of a certain component leads to the delay in the production. The solution is in making the substituents for the particular parts in case if they are unavailable for some time. It is advisable to check the lifetime of the component before using it in the design.
Use Decoupling Capacitors
Capacitors are the tiny electronic components that regulate the voltage flow through the circuit. Hence, you have to use a capacitor at every power pin. Even you can use in-ground capacitors for the large devices that have multiple power pins.
Don’t Forget Design Rule Checks(DRC)
This is the most important task that fabricant d'assemblage de circuits imprimés have to do before accomplishing the assembly task. Do check carefully the design rule before sending your design files to the manufacturers. Check your connections and routes considerately and procure the faults and flaws in the design.