A self-sensing tristate pad driver for control signals of multiple bus controllers

An output pad driver which tristates shortly after negation is presented in this paper. It is suitable for single-board computers where different bus controllers respond to different parts of the address map, and thus multiple components may individually drive handshaking signals to communicate with the processor. Since the operation of the pad driver requires only one internal control signal, it provides a simple solution to the targeted problem. Also, high-speed operation is achieved because the pad driver actively negates before tristating. Furthermore, a wide range of capacitive loads is supported because the pad driver senses its output voltage