[little knowledge] PCB proofing process

do pcb The purpose of proofing is to prepare the product before mass production , First make a small number of samples to test whether the product quality is qualified , To some extent, it can avoid risks for future mass production . that ,PCB What is the PCB proofing process ？

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First step ： Check the data

Before production ,PCB The circuit board factory will check the board making data provided by the customer , Including the size of the board 、 Process requirements, product quantity and other relevant data , The next step of production can only be carried out after reaching an agreement with the customer .

The second step ： Open the material

According to the information provided by the customer , On a plate that meets the requirements , Cut off small pieces to produce panels . Specific operation ： Big board → Press MI Cutting plate is required → Curium board → Beer fillet / Edging → Out of the board .

The third step ： drill hole

stay PCB Drill the required hole diameter at the corresponding position of the circuit board . Big board → Press MI Cutting plate is required → Curium board → Beer fillet / Edging → Out of the board .

Step four ： Heavy copper

A thin layer of copper is chemically deposited on the insulating hole . Specific operation ： Rough grind → Hanging board → Automatic copper wire → Lower board → Soak 1% rare H2SO4→ Thicken the copper .

Step five ： Graphic transfer

Transfer the image on the production film to the board . Specific operation ： Hemp board → Pressure film → Standing → Counterpoint → Exposure → Standing → Rush to the shadow → Check .

Step six ： Pattern plating

Electroplate a copper layer with required thickness and a gold nickel or tin layer with required thickness on the exposed copper skin or hole wall of the circuit pattern . Specific operation ： Board up → Degreasing → Wash twice with water → Micro erosion → Wash with water → pickling → Copper plating → Wash with water → Pickling → Tinning → Wash with water → Lower board .

Step seven ： Retreat the membrane

Apply the anti electroplating coating with NaOH Solution removal , Expose the non circuit copper layer .

Step eight ： etching

Remove the non circuit parts with chemical reagent copper .

Step nine ： Green

Transfer the green film graphics to the board , It mainly protects the circuit and prevents tin on the circuit when welding parts .

Step 10 ： character

stay PCB Legible characters are printed on the board . Specific operation ： After the green oil finally curium → Cool and let stand → Adjust the net → Print characters → Rear curium .

Step 11 ： Gilded fingers

Coat the plug finger with nickel of the required thickness / Gold layer , Make it more hardness and wear resistance .

The twelfth step ： forming

The customer needs the shape with the die stamping or CNC gongs machine gongs .

Thirteenth Step ： test

It is not easy to find by visual inspection because of an open circuit 、 Functional defects caused by short circuit, etc , It can be tested by flying needle tester .

The above is pcb The process of circuit board proofing , I hope it helped you ！

More content can be seen in official account. ：PCBA Information sharing