Quad Tri-state Buffers - National Semiconductor

This device DM54125 DM74125 contains four independent Gates each of which performs a non-inverting Buffer function. The outputs have the TRI-STATE feature. When enabled, the outputs exhibit the low impedance characteristics of a standard TTL output with additional drive capability at the high Logic level to per- mit the driving of bus lines without external pull-up resistors. When disabled, both the output Transistors are turned off presenting a high-impedance state to the bus line. Thus the output will act neither as a significant load nor as a driver. To minimize the possibility that two outputs will attempt to take a common bus to opposite Logic levels, the disable time is shorter than the enable time of the outputs. By National Semiconductor Corporation