A balanced line driver can also have an input signal called an "Enable" signal. 在平衡差分系统中，驱动器通过只传送一个信号的一对信号线来传送电压。
An unbalanced line is generally a single-conductor shielded cable with the center conductor carrying the signal and the shield at ground potential. 对于非平衡式信号线来说，就是一根被屏蔽了的信号线，这个中心信号线传输信号，且相对于地电势。
