54AC253 Datasheet | National Semiconductor

.. - 54ACT253 Dual 4-Input Multiplexer with TRI-STATE Outputs August 1998 - 54ACT253 Dual 4-Input Multiplexer with TRI-STATE ® Outputs General Description The ’AC/’ACT253 is a dual 4-input multiplexer with TRI-STATE outputs. It can select two bits of data from four sources using mon select inputs. The outputs may be individually switched to a high impedance state with a HIGH on the respective Output Enable (OE) inputs, allowing the outputs to interface directly with bus oriented systems. n n n n n Multifunction capability Noninverting TRI-STATE outputs Outputs source/sink 24 m A ’ACT253 has TTL-patible inputs Standard Military Drawing (SMD) - ’AC253: 5962-87693 - ’ACT253: 5962-87761 Features n ICC and IOZ reduced by 50% Logic Diagrams IEEE/IEC DS100285-1 DS100285-2 Pin Names I0a- I3a I0b- I3b S0, S1 OEa OEb Za, Zb Description Side A Data Inputs Side B Data Inputs mon Select Inputs Side A Output Enable Input Side B Output Enable Input TRI-STATE Outputs TRI-STATE ® is a registered trademark of National Semiconductor Corporation. FACT ® is a registered trademark of Fairchild Semiconductor Corporation. © 1998 National Semiconductor Corporation DS100285 .national. Connection Diagrams Pin Assignment for DIP and Flatpak Pin Assignment for LCC DS100285-3 DS100285-4 Functional Description The ’AC/’ACT253 contains two identical 4-input multiplexers with TRI-STATE outputs. They select two bits from four sources selected by mon Select inputs (S0, S1). The 4-input multiplexers have individual Output Enable (OEa, OEb) inputs which, when HIGH, force the outputs to a high impedance (High Z) state. This device is the logic implementation of a 2-pole, 4-position switch, where the position of the switch is determined by the logic levels supplied to the two select inputs. The logic equations for the outputs are shown: Za = OEa - (I0a - S1 - S0 + I1a - S1 - S0 + I2a -...