The method, a memory system and the memory module card for preventing local laser engraving ordinate nation of impedance in the vicinity of memory chips on the memory module

摘要

A signal line of a data bus has first wires on a first printed circuit board and a second wire on a second printed circuit board. The second printed circuit board is installed on the first printed circuit board, in order to the first and second wires to connect in series with one another, in order to keep the signal line to be erected. The semiconductor devices are connected with the second wire. In such a bus system is, the impedance of the second wire in accordance with the additional capacitance of the semiconductor device on the second printed circuit board is determined in such a way that the impedance of the first printed circuit board with the impedance of the second printed circuit board is harmonised.