The best way of minimizing ground impedance in a multicard system is to use another PCB as a backplane and have a ground plane( or even two- one analog, one digital) on that mother card.

• 为了降低多板连接的地线阻抗，最好的办法是专门设计一块背板（板）并且背板上要设置接地面（至设置模拟地和数字地两个接地面）此外，在背板与子板的连接器里要留出尽量多的引脚用于接地。