TL/F/11522
74VHC244
#
74VHCT244
Octal
Buffer/Line
Driver
with
TRI-STATE
Outputs
October 1995
74VHC244
#
74VHCT244
Octal Buffer/Line Driver with TRI-STATE
É
Outputs
General Description
The ’VHC/’VHCT244 is an advanced high speed CMOS oc-
tal bus buffer fabricated with silicon gate C
2
MOS technolo-
gy. It achieves high speed operation similar to equivalent
Bipolar Schottky TTL while maintaining the CMOS low pow-
er dissipation. The ’VHC/’VHCT244 is a non-inverting
TRI-STATE buffer having two active-low output enables.
These devices are designed to be used as TRI-STATE
memory address drivers, clock drivers, and bus oriented
transmitter/receivers.
An input protection circuit ensures that 0V – 7V can be ap-
plied to the input pins without regard to the supply voltage.
This device can be used to interface 5V to 3V systems and
two supply systems such as battery back up. This circuit
prevents device destruction due to mismatched supply and
input voltages.
Features
Y
High noise immunity:
VHC
V
NIH
e
V
NIL
e
28% V
CC
(min)
VHCT V
IH
e
2.0V, V
IL
e
0.8V
Y
Power down protection:
VHC
inputs only
VHCT inputs and outputs
Y
Low noise:
VHC
V
OLP
e
0.6V (typ)
VHCT V
OLP
e
0.7V (typ)
Y
Low power dissipation:
I
CC
e
4 mA (max)
@
T
A
e
25
§
C
Y
Balanced propagation delays: t
PLH
j
t
PHL
Y
Pin and function compatible with 74HC/HCT244
NOTE: ADD EXTERNAL PULL UP RESISTOR TO VHCT OUTPUTS TO
DRIVE CMOS INPUTS
Commercial
Package Number
Package Description
74VHC244M
M20B
20-Lead Molded JEDEC SOIC
74VHC244SJ
M20D
20-Lead Molded EIAJ SOIC
74VHC244MSC
MSC20
20-Lead Molded EIAJ Type 1 SSOP
74VHC244MTC
MTC20
20-Lead Molded JEDEC Type 1 TSSOP
74VHC244N
N20A
20-Lead Molded DIP
74VHCT244M
M20B
20-Lead Molded JEDEC SOIC
74VHCT244SJ
M20D
20-Lead Molded EIAJ SOIC
74VHCT244MTC
MTC20
20-Lead Molded JEDEC Type 1 TSSOP
74VHCT244N
N20A
20-Lead Molded DIP
Note:
Surface mount packages are also available on Tape and Reel. Specify by appending the suffix letter ‘‘X’’ to the ordering code.
EIAJ Type 1 SSOP available on Tape and Reel only, order MSCX.
Logic Symbol
IEEE/IEC
TL/F/11522 – 3
Connection Diagram
Pin Assignment for DIP,
SSOP, TSSOP and SOIC
TL/F/11522 – 1
Truth Tables
Inputs
Outputs
OE
1
I
n
(Pins 12, 14, 16, 18)
L
L
L
L
H
H
H
X
Z
Inputs
Outputs
OE
2
I
n
(Pins 3, 5, 7, 9)
L
L
L
L
H
H
H
X
Z
H e HIGH Voltage Level
I e Immaterial
L e LOW Voltage Level
Ze High
Impedance
Pin Names
Description
OE
1
, OE
2
TRI-STATE Output Enable Inputs
I
0
–I
7
Inputs
O
0
–O
7
TRI-STATE Outputs
TRI-STATE
É
is a registered trademark of National Semiconductor Corporation.
C1995 National Semiconductor Corporation
RRD-B30M125/Printed in U. S. A.
Absolute Maximum Ratings
(Note 1)
Supply Voltage (V
CC
)
b
0.5V to
a
7.0V
DC Input Voltage (V
IN
)
b
0.5V to
a
7.0V
DC Output Voltage (V
OUT
)
VHC
b
0.5V to V
CC
a
0.5V
VHCT*
b
0.5V to 7.0V
Input Diode Current (I
IK
)
b
20 mA
Output Diode Current (I
OK
)
VHC
g
20 mA
VHCT
b
20 mA
DC Output Current (I
OUT
)
g
25 mA
DC V
CC
/GND Current (I
CC
)
g
75 mA
Storage Temperature (T
STG
)
b
65
§
C to
a
150
§
C
Lead Temperature (T
L
)
(Soldering, 10 seconds)
260
§
C
*V
OUT
l
V
CC
only if output is in H or Z state.
Note 1:
Absolute Maximum Ratings are values beyond
which the device may be damaged or have its useful life
impaired. The databook specifications should be met, with-
out exception, to ensure that the system design is reliable
over its power supply, temperature, and output/input load-
ing variables. National does not recommend operation out-
side databook specifications.
Recommended Operating
Conditions
Supply Voltage (V
CC
)
VHC
2.0V to 5.5V
VHCT
4.5V to 5.5V
Input Voltage (V
IN
)
0V to
a
5.5V
Output Voltage (V
OUT
)
0V to V
CC
Operating Temperature (T
OPR
)
74VHC/VHCT
b
40
§
C to
a
85
§
C
Input Rise and Fall Time (t
r
, t
f
)
V
CC
e
3.3V
g
0.3V (VHC Only)
0 ns/V E 100 ns/V
V
CC
e
5.0V
g
0.5V
0 ns/V E 20 ns/V
DC Characteristics for ’VHC Family Devices
Symbol
Parameter
V
CC
(V)
74VHC
74VHC
Units
Conditions
T
A
e
25
§
C
T
A
e b
40
§
C
to
a
85
§
C
Min
Typ
Max
Min
Max
V
IH
High Level Input Voltage
2.0
1.5
1.5
3.0 – 5.5
0.7 V
CC
0.7 V
CC
V
V
IL
Low Level Input Voltage
2.0
0.5
0.5
3.0 – 5.5
0.3 V
CC
0.3 V
CC
V
V
OH
High Level Output Voltage
2.0
1.9
2.0
1.9
V
IN
e
V
IH
I
OH
e b
50 mA
3.0
2.9
3.0
2.9
V
or V
IL
4.5
4.4
4.5
4.4
3.0
2.58
2.48
V
I
OH
e b
4 mA
4.5
3.94
3.80
I
OH
e b
8 mA
V
OL
Low Level Output Voltage
2.0
0.0
0.1
0.1
V
IN
e
V
IH
I
OL
e
50 mA
3.0
0.0
0.1
0.1
V
or V
IL
4.5
0.0
0.1
0.1
3.0
0.36
0.44
V
I
OL
e
4 mA
4.5
0.36
0.44
I
OL
e
8 mA
2
DC Characteristics for ’VHC Family Devices
(Continued)
74VHC
74VHC
Symbol
Parameter
V
CC
T
A
e
25
§
C
T
A
e b
40
§
C
Units
Conditions
(V)
to
a
85
§
C
Min
Typ
Max
Min
Max
I
OZ
TRI-STATE Output Off-State Current
5.5
g
0.25
g
2.5
m
A
V
IN
e
V
IH
or V
IL
V
OUT
e
V
CC
or GND
I
IN
Input Leakage Current
0 – 5.5
g
0.1
g
1.0
m
A
V
IN
e
5.5V or GND
I
CC
Quiescent Supply Current
5.5
4.0
40.0
m
A
V
IN
e
V
CC
or GND
DC Characteristics for ’VHC Family Devices
V
CC
(V)
74VHC
Symbol
Parameter
T
A
e
25
§
C
Units
Conditions
Typ
Limits
V
OLP
**
Quiet Output Maximum
5.0
0.6
0.9
V
C
L
e
50 pF
Dynamic V
OL
V
OLV
**
Quiet Output Minimum
5.0
b
0.6
b
0.9
V
C
L
e
50 pF
Dynamic V
OL
V
IHD
**
Minimum High Level
5.0
3.5
V
C
L
e
50 pF
Dynamic Input Voltage
V
ILD
**
Maximum High Level
5.0
1.5
V
C
L
e
50 pF
Dynamic Input Voltage
**Parameter guaranteed by design.
3
DC Characteristics for ’VHCT Family Devices
Symbol
Parameter
V
CC
(V)
74VHC
74VHC
Units
Conditions
T
A
e
25
§
C
T
A
e b
40
§
C
to
a
85
§
C
Min
Typ
Max
Min
Max
V
IH
High Level Input
4.5
2.0
2.0
V
Voltage
5.5
2.0
2.0
V
IL
Low Level Input
5.5
4.5
0.8
0.8
0.8
0.8
V
Voltage
V
OH
High Level
4.5
3.15
3.65
3.15
V
V
IN
e
V
IH
I
OH
e b
50 mA
Output Voltage
4.5
2.5
2.4
or V
IL
I
OH
e b
8 mA
V
OL
Low Level
4.5
0.0
0.1
0.1
V
V
IN
e
V
IH
I
OL
e
50 mA
Output Voltage
4.5
0.36
0.44
or V
IL
I
OL
e
8 mA
I
OZ
TRI-STATE
V
IN
e
V
IH
or V
IL
Output
5.5
g
0.25
g
2.5
m
A
V
OUT
e
V
CC
or GND
Off-State
Current
I
IN
Input
V
IN
e
5.5V or GND
Leakage
0 – 5.5
g
0.1
g
1.0
m
A
Current
I
CC
Quiescent
V
IN
e
V
CC
or GND
Supply
5.5
4.0
40.0
m
A
Current
I
CCT
Maximum
5.5
1.35
1.50
mA
V
IN
e
3.4V, Other
I
CC
/Input
Inputs
e
V
CC
or GND
I
OPD
Output
V
OUT
e
5.5V
Leakage
0.0
a
0.5
a
5.0
m
A
(Power Down
State)
DC Characteristics for ’VHCT Family Devices:
Symbol
Parameter
V
CC
(V)
74VHCT
Units
Conditions
T
A
e
25
§
C
Typ
Limits
V
OLP
**
Quiet Output Maximum
0.7
1.0
V
C
L
e
50 pF
Dynamic V
OL
V
OLV
**
Quiet Output Minimum
b
0.7
b
1.0
V
C
L
e
50 pF
Dynamic V
OL
V
IHD
**
Minimum High Level
2.0
V
C
L
e
50 pF
Dynamic Input Voltage
V
ILD
**
Maximum High Level
0.8
V
C
L
e
50 pF
Dynamic Input Voltage
**Parameter guaranteed by design.
4
AC Electrical Characteristics for ’VHC Family Devices:
Symbol
Parameter
V
CC
(V)
74VHC
74VHC
Units
Conditions
T
A
e
25
§
C
T
A
e b
40
§
C
to
a
85
§
C
Min
Typ
Max
Min
Max
t
PLH
,
Propagation Delay Time
3.3
g
0.3
5.8
8.4
1.0
10.0
ns
C
L
e
15 pF
t
PHL
8.3
11.9
1.0
13.5
C
L
e
50 pF
5.0
g
0.5
3.9
5.5
1.0
6.5
ns
C
L
e
15 pF
5.4
7.5
1.0
8.5
C
L
e
50 pF
t
PZL
,
TRI-STATE Output Enable
3.3
g
0.3
6.6
10.6
1.0
12.5
ns
R
L
e
1 kX
C
L
e
15 pF
Time
t
PZH
9.1
14.1
1.0
16.0
C
L
e
50 pF
5.0
g
0.5
4.7
7.3
1.0
8.5
ns
C
L
e
15 pF
6.2
9.3
1.0
10.5
C
L
e
50 pF
t
PLZ
,
TRI-STATE
3.3
g
0.3
10.3
14.0
1.0
16.0
ns
R
L
e
1 kX
C
L
e
50 pF
t
PHZ
Output
5.0
g
0.5
6.7
9.2
1.0
10.5
C
L
e
50 pF
Disable Time
t
OSLH
,
Output to Output Skew
3.3
g
0.3
1.5
1.5
ns
(Note 1)
C
L
e
50 pF
t
OSHL
5.0
g
0.5
1.0
1.0
C
L
e
50 pF
C
IN
Input Capacitance
4
10
10
pF
V
CC
e
Open
C
OUT
Output Capacitance
6
pF
V
CC
e
5.0V
C
PD
Power Dissipation Capacitance
19
pF
(Note 2)
Note 1:
Parameter guaranteed by design. t
OSLH
e
l
t
PLHmax
b
t
PLHmin
l
; t
OSHL
e
l
t
PHLmax
b
t
PHLmin
l
.
Note 2:
C
PD
is defined as the value of the internal equivalent capacitance which is calculated from the operating current consumption without load. Average
operating current can be obtained by the equation: I
CC
(OPR.) e C
PD
* V
CC
* f
IN
a
I
CC
/8 (per bit).
5
AC Electrical Characteristics for ’VHCT Family Devices
Symbol
Parameter
V
CC
(V)
74VHCT
74VHCT
Units
Conditions
T
A
e
25
§
C
T
A
e b
40
§
C
to
a
85
§
C
Min
Typ
Max
Min
Max
t
PLH
,
Propagation Delay Time
5.0
g
0.5
5.4
7.4
1.0
8.5
ns
C
L
e
15 pF
t
PHL
5.9
8.4
1.0
9.5
C
L
e
50 pF
t
PZL
,
TRI-STATE Output Enable Time
5.0
g
0.5
7.7
10.4
1.0
12.0
ns
R
L
e
1 kX
C
L
e
15 pF
t
PZH
8.2
11.4
1.0
13.0
C
L
e
50 pF
t
PLZ
,
TRI-STATE
5.0
g
0.5
R
L
e
1 kX
C
L
e
50 pF
t
PHZ
Output
8.8
11.4
1.0
13.0
ns
Disable Time
t
OSLH
,
Output to Output Skew
5.0
g
0.5
1.0
1.0
ns
(Note 1)
C
L
e
50 pF
t
OSHL
C
IN
Input Capacitance
4
10
10
pF
V
CC
e
Open
C
OUT
Output Capacitance
9
pF
V
CC
e
5.0V
C
PD
Power Dissipation Capacitance
18
pF
(Note 2)
Note 1:
Parameter guaranteed by design. t
OSLH
e
l
t
PLHmax
b
t
PLHmin
l
; t
OSHL
e
l
t
PHLmax
b
t
PHLmin
l
.
Note 2:
C
PD
is defined as the value of the internal equivalent capacitance which is calculated from the operating current consumption without load. Average
operating current can be obtained by the equation: I
CC
(OPR.) e C
PD
* V
CC
* f
IN
a
I
CC
/8 (per bit).
6
Ordering Information
The device number is used to form part of a simplified purchasing code, where the package type and temperature range are
defined as follows:
TL/F/11522 – 4
7
Physical Dimensions
inches (millimeters)
20-Lead Small Outline Integrated Circuit JEDEC SOIC (M)
Order Number 74VHC244M, 74VHC244MX, 74VHCT244M or 74VHCT244MX
NS Package Number M20B
20-Lead Small Outline Integrated Circuit-EIAJ SOIC (SJ)
Order Number 74VHC244SJ, 74VHC244SJX, 74VHCT244SJ or 74VHCT244SJX
NS Package Number M20D
8
Physical Dimensions
millimeters
20-Lead Plastic EIAJ SSOP Type I (MSC)
Order Number 74VHC244MSCX
NS Package Number MSC20
20-Lead Plastic JEDEC TSSOP Type I (MTC)
Order Number 74VHC244MTC, 74VHC244MTCX, 74VHCT244MTC or 74VHCT244MTCX
NS Package Number MTC20
9
74VHC244
#
74VHCT244
Octal
Buffer/Line
Driver
with
TRI-STATE
Outputs
Physical Dimensions
(millimeters) (Continued)
20-Lead Molded DIP
Order Number 74VHC244N or 74VHCT244N
NS Package Number N20A
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL
SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
2. A critical component is any component of a life
systems which, (a) are intended for surgical implant
support device or system whose failure to perform can
into the body, or (b) support or sustain life, and whose
be reasonably expected to cause the failure of the life
failure to perform, when properly used in accordance
support device or system, or to affect its safety or
with instructions for use provided in the labeling, can
effectiveness.
be reasonably expected to result in a significant injury
to the user.
National Semiconductor
National Semiconductor
National Semiconductor
National Semiconductor
Corporation
Europe
Hong Kong Ltd.
Japan Ltd.
1111 West Bardin Road
Fax: (
a
49) 0-180-530 85 86
13th Floor, Straight Block,
Tel: 81-043-299-2309
Arlington, TX 76017
Email: cnjwge
@
tevm2.nsc.com
Ocean Centre, 5 Canton Rd.
Fax: 81-043-299-2408
Tel: 1(800) 272-9959
Deutsch Tel: (
a
49) 0-180-530 85 85
Tsimshatsui, Kowloon
Fax: 1(800) 737-7018
English
Tel: (
a
49) 0-180-532 78 32
Hong Kong
Fran
3ais Tel: (
a
49) 0-180-532 93 58
Tel: (852) 2737-1600
Italiano
Tel: (
a
49) 0-180-534 16 80
Fax: (852) 2736-9960
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.