54LS244 DM74LS244 Octal TRI-STATE Buffers Line Drivers Line Receivers
August 1989
54LS244 DM74LS244 Octal TRI-STATE
Buffers Line Drivers Line Receivers
General Description
These buffers line drivers are designed to improve both the
performance and PC board density of TRI-STATE buffers
drivers employed as memory-address drivers clock drivers
and bus-oriented transmitters receivers Featuring 400 mV
of hysteresis at each low current PNP data line input they
provide improved noise rejection and high fanout outputs
and can be used to drive terminated lines down to 133X
Y
Y
Y
Features
Y
Y
Y
Y
Y
TRI-STATE outputs drive bus lines directly
PNP inputs reduce DC loading on bus lines
Hysteresis at data inputs improves noise margins
Typical I
OL
(sink current)
54LS
12 mA
74LS
24 mA
Typical I
OH
(source current)
b
12 mA
54LS
b
15 mA
74LS
Typical propagation delay times
Inverting
10 5 ns
Noninverting 12 ns
Typical enable disable time 18 ns
Typical power dissipation (enabled)
Inverting
130 mW
Noninverting 135 mW
Connection Diagram
Dual-In-Line Package
TL F 8442 鈥?1
Order Number 54LS244DMQB 54LS244FMQB 54LS244LMQB
DM74LS244WM or DM74LS244N
See NS Package Number E20A J20A M20B N20A or W20A
Function Table
Inputs
G
L
L
H
A
L
H
X
Output
Y
L
H
Z
L
e
Low Logic Level
H
e
High Logic Level
X
e
Either Low or High Logic Level
Z
e
High Impedance
TRI-STATE is a registered trademark of National Semiconductor Corporation
C
1995 National Semiconductor Corporation
TL F 8442
RRD-B30M105 Printed in U S A
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