As is the case for individual lines, multiple lines can also be series or parallel terminated. We see an arrangement of parallel termination in figure 2.20. It is quite obvious that the step voltage Vu(t) is simultaneously impressed on all n transmission lines. The voltage propagates to the end of each line where it is absorbed without reflection. This connection does not require a great deal of study. The only drawback of this circuit is that in the high state the voltage source on the left has to supply a current equal to nV/Z 0​ . If the high state voltage is 5 V, as would be the case for TTL and CMOS, then for five printed-circuit-board traces with a Z 0​ =50Ω the line driver would have to supply a current of 500 mA. This is a very substantial (onehalf ampere) current demand on the driver and also on the power supply of the system. Figure 2.20 Multiple lines terminated in parallel.