MC74AC157DG ON Semiconductor

MC74AC157, MC74ACT157 Quad 2-Input Multiplexer The MC74AC157/74ACT157 is a highspeed quad 2input multiplexer. Four bits of data from two sources can be selected using the common Select and Enable inputs. The four outputs present the selected data in the true (noninverted) form. The MC74AC157/74ACT157 can also be used as a function www.onsemi.com generator. MARKING Features DIAGRAMS Outputs Source/Sink 24 mA 16 ACT157 Has TTL Compatible Inputs SOIC16 xxx157G These are PbFree Devices D SUFFIX 16 AWLYWW CASE 751B 1 1 16 V E I I Z I I Z CC 0c 1c c 0d 1d d xxx TSSOP16 16 15 14 13 12 11 10 9 157 16 DT SUFFIX ALYW CASE 948F 1 1 xxx = AC or ACT A = Assembly Location WL or L = Wafer Lot 1 2 3 4 567 8 Y = Year WW or W = Work Week SI I Z I I Z GND 0a 1a a 0b 1b b G or = PbFree Package (Note: Microdot may be in either location) Figure 1. Pinout: 16Lead Packages Conductors (Top View) PIN NAMES TRUTH TABLE PIN FUNCTION Inputs Outputs I I Source 0 Data Inputs 0a 0d E S I I Z 0 1 I I Source 0 Data Inputs 1a 1d H X X X L E Enable Input L H X L L S Select Input L H X H H L L L X L Outputs Z Z a d L L H X H H = HIGH Voltage Level L = LOW Voltage Level X = Immaterial ORDERING INFORMATION See detailed ordering and shipping information in the package dimensions section on page 6 of this data sheet. Semiconductor Components Industries, LLC, 2015 1 Publication Order Number: January, 2015 Rev. 8 MC74AC157/DMC74AC157, MC74ACT157 EI I I I I I I I 0a 1a 0b 1b 0c 1c 0d 1d S Z Z Z Z a b c d Figure 2. Logic Symbol FUNCTIONAL DESCRIPTION Z = E(I S+I S) a 1a 0a Z = E(I S+I S) b 1b 0b The MC74AC157/74ACT157 is a quad 2input Z = E(I S+I S) c 1c 0c multiplexer. It selects four bits of data from two sources Z = E(I S+I S) d 1d 0d under the control of a common Select input (S). The Enable A common use of the MC74AC157/74ACT157 is the input (E) is activeLOW. When E is HIGH, all of the outputs moving of data from two groups of registers to four common (Z) are forced LOW regardless of all other inputs. The output busses. The particular register from which the data MC74AC157/74ACT157 is the logic implementation of a comes is determined by the state of the Select input. A less 4pole, 2position switch where the position of the switch obvious use is as a function generator. The is determined by the logic levels supplied to the Select input. MC74AC157/74ACT157 can generate any four of the The logic equations for the outputs are shown below: sixteen different functions of two variables with one variable common. This is useful for implementing gating functions. I I I I I I I I E S 0a 1a 0b 1b 0c 1c 0d 1d Z Z Z Z a b c d NOTE: This diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays. Figure 3. Logic Diagram www.onsemi.com 2