单选

PCB设计不当,会对电子设备的可靠性产生不良影响。以下关于PCB地线设计方法描述错误的是(24)。

  • A.只由数字电路组成的PCB的地线系统时,可将接地线做成闭环路
  • B.电路板上既有高速逻辑电路,又有线性电路时,应尽量加大线性电路的接地面积
  • C.接地线应尽可能加粗,使它能通过3倍于PCB的允许电流
  • D.在低频电路中,通常信号的工作频率小于1 MHz,它的布线和元件间的电感影响较小,而接地电路形成的环流对干扰影响较大,因而应采用就近多点接地
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