Printed circuit boards are the backbone of all modern electronic devices, let us discuss what a pcb is and how these small circuits are produced, initially electronic components were manufactured and connected to each other manually using wires in point to point construction this manual construction caused errors and difficulties in increased production, besides because the circuit was so complicated that the work of repairing a broken circuit was an unreliable and tedious task, in the year one thousand nine hundred and thirty six pol iceland a genius technician working in a newspaper company began to realize the hurdle.
He invented the concept of printing copper circuits conducive to a non-constructive board as shown here, then connected components via traces. This was the first PCB produced, but modern PCBs look like these are much more sophisticated, small and complex. Modern PCB manufacturing started from simple flat copper sheets. , let's see how this sheet develops into a sophisticated electronic device in a detailed logical way.
To begin with this full layer of copper is laminated on a flat sheet of insulating glass fiber, the glass fiber provides mechanical support to the PCB. This glass fiber will remain on the PCB until the end of the manufacturing process. This arrangement is first sent to drilling along with the protective aluminum sheet, here several holes called registration holes in Bogor.
These holes serve as reference points for the next alignment process, meanwhile a technician designs circuits using computer-assisted simulations here are some pcb design software that generates a design file called fall geber, the value server contains details of the 3d pcb model, using the design file This drilling machine makes different holes.
These holes are later used to attach the components to the board, after drilling the board is cleaned so that no drilling residue is left behind, now the most important step is the production of these small and complex copper traces the best way to do this is by a chemical process called etching i.e. you have to cover the copper plate with the system mask, this system mask will have the same circular pattern you want.
Now if you dip this array in an alkaline solution at sixty to one hundred and twenty degrees centigrade the copper arya exposed by the system mask will dissolve or strain, once this process is complete, the protective mask will also wash off so only the remaining copper residue is needed. , the series of prints on the system masks used in this process were clearly made with the help of fall geber a UV-based technique was used to attach the masks to copper plates if necessary to mass manufacture several masks made on a single sheet.
As you can see the traces of copper are very thin almost invisible to the naked eye, to check the quality of the traces of copper the board must be checked, an operator with an optical inspection machine checks the quality of the printed board by taking a picture of it and comparing it to the design file, the machine will check for traces for damaged or short circuit and pcb with faulty short circuit bungee is rejected.
If there are no problems then the board is moved to the next step, have you ever wondered why the pcb is always green, this is to protect the board from oxidation and exposure to dust, a protective layer of felt solder mask is installed on top of the board, this layer gives the board its green color has been universally adopted.
Copper traces are hidden under a green layer after this operation this new added green resin is insulating, you can clearly see that the resin will block the connection between the copper traces on the edge of the hole and the component, to avoid this problem we have to remove the solder mask from the edge of the mask The solder that we add will stick to the copper plate only if it is subjected to a UV process.
So the trick is simple, just cover the edge area of the hole with a chemical resistant mask and do the uv process, after this when you do chemical immersion the green mask on the edge area will be removed, as the last step the shield screen is printed which is nothing but a visible layer of ink traces used to identify the components of the pcb, sign, logo, symbol and so on.
Finished we have made the pcb starting from a simple copper plate, your pcb is ready to be sent to the component industry then the components are installed and soldered using molten tin, this process attaches the components to the copper pads on the board, then the final flying pro test is carried out to check the connectivity between all trace components and bearings.
The pcb technology we are studying today is tht type although this technology is good for educational purposes tht is almost out of date the latest smt based pcb technology we will discuss this in a separate article to become a contributing member to this channel press the support button accept. love
Posting Komentar