Three-State Off-Chip Driver
Original Publication Date: 1983-Dec-01
Included in the Prior Art Database: 2005-Feb-07
This article describes a three-state current switch/push-pull off-chip driver circuit for use in high performance bipolar integrated circuit chips. The circuit features one to three inputs for logic OR/NOR functions, inputs that may be used as chip receivers, a disable input to set the outputs into a high impedance state, and symmetrical circuit topology for in-phase only, out-phase only or both-phase outputs. The circuit may also be used in bidirectional nets (a driver and a receiver at each end of the net) with over-current limiting and protection. Fig. 1 shows the circuit schematic, and Fig. 2 shows its logical function.