What is the tolerance range of the size of the copper foil of the PCB board?
The specification of the substrate thickness and deviation is divided into A/K (commonly known as 1), B/L (commonly known as grade 2), C/M (commonly known as the 3 level), D. The thickness of A, B, C level is the thickness of the clad metal foil, the thickness of K, L and M is the thickness of the metal foil after the laminate, and the D level is used to measure the minimum thickness of the substrate.
With the progress of electronic technology, the user is the higher of the CCL thickness and single point deviation requirements are many, CCL factory with thickness and deviation specification IPC-4101A "rigid and multilayer printed circuit board substrate for general specification" in.
Copper clad laminate national standard: GB4723~4725 "printed circuit copper clad laminate", as a result of years of revision, the standard thickness of the copper clad plate, single point deviation requirements are relatively loose.
