Intel 386 manual 1111

PHYSICAL DESIGN AND DEBUGGING

DriverReceiver

231732i11-16

Figure 11-16. A.C. Termination

11.4.2.1.6 Active Termination

These terminations consist of resistors that are connected between the inputs and out- puts of buffer drivers as shown in Figure 11-17.

The main advantage of this technique is that it can tolerate large impedance variations and this tolerance is valuable when tri-state drivers are connected to backplane buses. However, the terminations are costly, and the signals that are produced are not as clean

PC Boards in Connectors

Backplane

	1111
	One Line of Backplane Bus
Active Terminati~n	Active Termination

231732i11-17

Figure 11-17. Active Termination

11-21