Testing of Tri State Driver Circuits
Original Publication Date: 1981-Feb-01
Included in the Prior Art Database: 2005-Feb-10
Tri-state drivers (TSDs) are well known circuits whose outputs may be one of three possible states: logic 1, logic 0, and "high impedance" states (Fig. 1). Fig. 1A is a truth table for the TSD of Fig. 1. These circuits are commonly used in conjunction with external signal receivers, and play an important role in facilitating communication between logic and memory within a system (Fig. 2). By setting the TSD in the high impedance state, a read/write operation may be Performed through the same data bus line, and data may be transmitted directly to the receiver without interference from the TSD.