Fairchild Semiconductor DM74LS244WMX, DM74LS244WM, DM74LS244SJX, DM74LS244SJ, DM74LS244N Datasheet
...
© 2000 Fairchild Semiconductor Corporation DS008442 www.fairchildsemi.com
August 1986
Revised March 2000
DM74LS244 Octal 3-STATE Buffer/Line Driver/Line Receiver
DM74LS244
Octal 3-STATE Buffer/Line Driver/Line Receiver
General Description
These buffers/line drivers are designed to improve both the
performance and PC board density of 3-STATE buffers/
drivers employed as memor y-address drivers, clock drivers, and bus-oriented transmitters/receivers. Featuring 400
mV of hysteresis at each low cu rrent PNP data lin e input,
they provide improve d noise rej ection and h igh fan out outputs and can be used to drive terminated li nes down to
133Ω.
Features
■ 3-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) 24 mA
■ Typical I
OH
(source current) −15 mA
■ 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
Ordering Code:
Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” to the ordering code.
Connection Diagram Function Table
L = LOW Logic Level
H = HIGH Logic Level
X = Either LOW or HIGH Logic Level
Z = High Impedance
Order Number Package Number Package Description
DM74LS244WM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74LS244SJ M20D 20-Lead Small Outline Pac kage (SOP), EIAJ TYPE II, 5.3mm Wide
DM74LS244N N20A 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Inputs Output
G
AY
LLL
LHH
HXZ
www.fairchildsemi.com 2
DM74LS244
Absolute Maximum Ratings(Note 1)
Note 1: The “Absolute Maximum Ratin gs” are those v alues beyon d which
the safety of the dev ice cannot be guaranteed. T he device sh ould not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommend ed O peratin g Cond itions” t able w ill defin e the co ndition s
for actual device operation.
Recommended Operating Conditions
Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Note 2: All typicals are at VCC = 5V, TA = 25°C.
Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Supply Voltage 7V
Input Voltage 7V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature Range −65°C to +150°C
Symbol Parameter Min Nom Max Units
V
CC
Supply Voltage 4.75 5 5.25 V
V
IH
HIGH Level Input Voltage 2 V
V
IL
LOW Level Input Voltage 0.8 V
I
OH
HIGH Level Output Current −15 mA
I
OL
LOW Level Output Current 24 mA
T
A
Free Air Operating Temperature 0 70 °C
Symbol Parameter Conditions
Min Typ Max
Units
(Note 2)
V
I
Input Clamp Voltage VCC = Min, II = −18 mA −1.5 V
HYS Hysteresis (VT+ − VT−)V
CC
= Min 0.2 0.4 V
Data Inputs Only
V
OH
HIGH Level Output Voltage VCC = Min, VIH = Min
2.7
VIL = Max, IOH = −1 mA
VCC = Min, VIH = Min
2.4 3.4 V
VIL = Max, IOH = −3 mA
VCC = Min, VIH = Min
2
VIL = 0.5V, IOH = Max
V
OL
LOW Level Output Voltage VCC = Min IOL = 12 mA 0.4
VVIL = Max IOL = Max 0.5
VIH = Min
I
OZH
Off-State Output Current, VCC = Max VO = 2.7V 20 µA
HIGH Level Voltage Applied VIL = Max
I
OZL
Off-State Output Current, VIH = Min VO = 0.4V −20 µA
LOW Level Voltage Applied
I
I
Input Current at Maximum VCC = Max VI = 7V 0.1 mA
Input Voltage
I
IH
HIGH Level Input Current VCC = Max VI = 2.7V 20 µA
I
IL
LOW Level Input Current VCC = Max VI = 0.4V −0.5 −200 µA
I
OS
Short Circuit Output Current VCC = Max (Note 3) −40 −225 mA
I
CC
Supply Current VCC = Max, Outputs HIGH 13 23
Outputs Open Outputs LOW 27 46 mA
Outputs Disabled 32 54
Loading...