Problem

For each of the R1 and R2 pairs in Exercise, determine whether the termination can be prop...

For each of the R1 and R2 pairs in Exercise, determine whether the termination can be properly driven by a three-stale output in each of the following logic families: 74LS, 74S, 74FCT-T. For proper operation, the family’s IOL and IOH specs must not be exceeded when VOL = VOLmax and VOH = VOHmin respectively.

Exercise

A Thévenin termination for an open-collector or three-state bus has the structure shown in Figure (a).The idea is that, with appropriate values of R1 and R2, this circuit is equivalent to the termination in (b) for any desired values of V and R. The value of V determines the voltage on the bus when no device is driving it, and the value of R is selected to match the characteristic impedance of the bus for transmission-line purposes (Section Zo at DDPPonline). For each of the following pairs of V and R, determine the required values of R1 and R2.