DM74AS157 Datasheet, PDF (1/7 Pages) Fairchild Semiconductor – Quad 1 of 2 Line Data Selector/Multiplexer

April 1984
Revised March 2000
DM74AS157 • DM74AS158
Quad 1 of 2 Line Data Selector/Multiplexer
General Description
These data selectors/multiplexers contain inverters and
drivers to supply full on-chip data selection to the four out-
put gates. A separate STROBE input is provided. A 4-bit
word is selected from one of two sources and is routed to
the four outputs. The AS157 presents true data whereas
the AS158 presents inverted data to minimize propagation
delay time.
Features
s Switching specifications at 50 pF
s Switching specifications guaranteed over full tempera-
ture and V_CC range
s Advanced oxide-isolated, ion-implanted Schottky TTL
process
s Functionally and pin for pin compatible with Schottky,
low power Schottky, and advanced low power Schottky
TTL counterpart
s Improved AC performance over Schottky, low power
Schottky, and advanced low power Schottky counter-
parts
s Expand any data input point
s Multiplex dual data buses
s General four functions of two variables (one variable is
common)
s Source programmable counters
Ordering Code:
Order Number Package Number
Package Description
DM74AS157M
M16A
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow
DM74AS157SJX
M16D
16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
DM74AS157N
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
DM74AS158M
M16A
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow
DM74AS158N
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
Connection Diagram
Function Table
Inputs
STROBE Select A
H
X
X
L
L
L
L
L
H
L
H
X
L
H
X
H = HIGH Level
L = LOW Level
X = Don't Care
Output Y
B DM74AS157 DM74AS158
X
L
H
X
L
H
X
H
L
L
L
H
H
H
L
© 2000 Fairchild Semiconductor Corporation DS006290
www.fairchildsemi.com