Method of manufacturing a multilayer transformer printed circuit board (PCB) for an electric car

A method of manufacturing a multilayer transformer printed circuit board (PCB) for an electric car, comprising:

• a first step of cutting a source material for inner layer of the transformer PCB to a given standard size and forming an inner layer circuit on the cut source material through a conductive patterning process including a photosensitive film process;
• a second step of performing a black oxide process on the inner layer circuit of the transformer PCB after the first step;
• a third step of performing a lamination process including laminating a source material forming an outer layer on top of the inner layer circuit formed on the inner layer of the transformer PCB after the second step;
• a fourth step of cutting the source material of the outer layer laminated on top of the inner layer of the transformer PCB to a given standard size and forming an outer layer circuit through a conductive patterning process including a photosensitive film process after the third step;
• a fifth step of forming a photo solder resist (PSR)-printed layer coated with a PSR ink along each of the 1st, 2nd, 3rd, 4th and 5th printing directions on a top surface of the outer layer circuit on the top of the transformer PCB formed thereon by the first step to the fourth step;
• and
• a sixth step of performing gold plating on at least a portion of the outer layer circuit on the top of the transformer PCB having the PSR-printed layer formed thereon, and marking, and appearance processing, mounting various parts on the transformer PCB to finish the transformer PCB for an electric car after the fifth step wherein the first step further comprises:
• an inner layer circuit connection operation of horizontally forming first and second connecting copper tabs on both surfaces of the inner layer of the transformer PCB using a copper material so that the copper material has a thickness of 360 μm, and connecting battery cells to inner layer circuits,
• wherein the fourth step further comprises:
• an outer layer circuit connection operation of horizontally forming third and fourth connecting copper tabs on both surfaces of the outer layers laminated to the inner layers of the transformer PCB using a copper material so that the copper material has a thickness of 360 μm, and connecting the battery cells to outer layer circuits, and
• wherein the sixth step further comprises:
• a plating operation of plating top surfaces of the first, second, third, and fourth connecting copper tabs with nickel at a thicknesses of 3 to 5 μm and gold at a thicknesses of 0.03 to 0.05 μm.