What are Plated Through Holes

In through-hole technology, the components are mounted on the PCB board by inserting their leads through the respective hole. These holes are called through holes since they are drilled from the top to the bottom of the board.

When using Plated Through Holes, as the name suggests, the inner wall of the holes is covered with a thin layer of Copper, which makes the entire inner hole area conductive. 

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