Buffer with drive characteristics controllable by software

摘要

A buffer with drive characteristics controllable by software includes a plurality of MOSFETs connected in parallel between input and output terminals of the buffer. The drains of the MOSFETs are coupled to the output terminal, whereas the gates of the MOSFETs are connected through logic gate circuits to the input terminal and to corresponding registers of a programmable controller. The gates of the MOSFETs go high or low in order to turn the MOSFETs on and off in accordance with a preset program loaded by an external programming device. The number of MOSFETs turned on is a determining factor for the strength and rise time of the signals formed by the buffer.