74HC244; 74HCT244
Octal buffer/line driver; 3-state
Rev. 4 — 24 September 2012
Product data sheet
1. General description
The 74HC244; 74HCT244 is an 8-bit buffer/line driver with 3-state outputs. The device
can be used as two 4-bit buffers or one 8-bit buffer. The device features two output
enables (1OE and 2OE), each controlling four of the 3-state outputs. A HIGH on nOE
causes the outputs to assume a high-impedance OFF-state. Inputs include clamp diodes
that enable the use of current limiting resistors to interface inputs to voltages in excess of
V
CC
.
2. Features and benefits
Input levels:
For 74HC244: CMOS level
For 74HCT244: TTL level
Octal bus interface
Non-inverting 3-state outputs
Complies with JEDEC standard no. 7 A
ESD protection:
HBM JESD22-A114F exceeds 2000 V
MM JESD22-A115-A exceeds 200 V
Multiple package options
Specified from
40 C
to +85
C
and
40 C
to +125
C
3. Ordering information
Table 1.
Ordering information
Package
Temperature range
74HC244N
74HCT244N
74HC244D
74HCT244D
74HC244DB
74HCT244DB
74HC244PW
74HCT244PW
74HC244BQ
74HCT244BQ
40 C
to +125
C
40 C
to +125
C
TSSOP20
40 C
to +125
C
SSOP20
40 C
to +125
C
SO20
plastic small outline package; 20 leads;
body width 7.5 mm
plastic shrink small outline package; 20 leads;
body width 5.3 mm
plastic thin shrink small outline package; 20 leads;
body width 4.4 mm
SOT163-1
SOT339-1
SOT360-1
40 C
to +125
C
Name
DIP20
Description
plastic dual in-line package; 20 leads (300 mil)
Version
SOT146-1
Type number
DHVQFN20 plastic dual-in-line compatible thermal enhanced
SOT764-1
very thin quad flat package; no leads; 20 terminals;
body 2.5
4.5
0.85 mm
NXP Semiconductors
74HC244; 74HCT244
Octal buffer/line driver; 3-state
4. Functional diagram
2
1A0
1Y0
18
4
1A1
1Y1
16
6
1A2
1Y2
14
8
1
1A3
1OE
1Y3
12
17
2A0
2Y0
3
15
2A1
2Y1
5
13
2A2
2Y2
7
11
19
2A3
2OE
2Y3
9
mna875
Fig 1.
Functional diagram
1
EN
18
16
14
12
1A0
2
18
1Y0
2A0
17
3
2Y0
2
4
1A1
4
16
1Y1
2A1
15
5
2Y1
6
8
1A2
6
14
1Y2
2A2
13
7
2Y2
19
EN
9
7
5
3
mna873
1A3
1OE
8
1
12
1Y3
2A3
2OE
11
19
9
2Y3
11
13
mna874
15
17
Fig 2.
Logic symbol
Fig 3.
IEC logic symbol
74HC_HCT244
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2012. All rights reserved.
Product data sheet
Rev. 4 — 24 September 2012
2 of 18
NXP Semiconductors
74HC244; 74HCT244
Octal buffer/line driver; 3-state
5. Pinning information
5.1 Pinning
74HC244
74HCT244
1OE
1A0
2Y0
1A1
2Y1
1A2
2Y2
1A3
2Y3
1
2
3
4
5
6
7
8
9
20 V
CC
19 2OE
18 1Y0
17 2A0
16 1Y1
15 2A1
14 1Y2
13 2A2
12 1Y3
11 2A3
001aae011
74HC244
74HCT244
1OE
2
3
4
5
6
7
8
9
GND 10
2A3 11
GND
(1)
1
terminal 1
index area
1A0
2Y0
1A1
2Y1
1A2
2Y2
1A3
2Y3
20 V
CC
19 2OE
18 1Y0
17 2A0
16 1Y1
15 2A1
14 1Y2
13 2A2
12 1Y3
GND 10
001aae012
Transparent top view
(1) This is not a supply pin. The substrate is attached to this
pad using conductive die attach material. There is no
electrical or mechanical requirement to solder this pad.
However, if it is soldered, the solder land should remain
floating or be connected to GND.
Fig 4.
Pin configuration DIP20, SO20, (T)SSOP20
Fig 5.
Pin configuration DHVQFN20
5.2 Pin description
Table 2.
Symbol
1OE, 2OE
1A0, 1A1, 1A2, 1A3
2Y0, 2Y1, 2Y2, 2Y3
GND
2A0, 2A1, 2A2, 2A3
1Y0, 1Y1, 1Y2, 1Y3
V
CC
Pin description
Pin
1, 19
2, 4, 6, 8
3, 5, 7, 9
10
17, 15, 13, 11
18, 16, 14, 12
20
Description
output enable input (active LOW)
data input
bus output
ground (0 V)
data input
bus output
supply voltage
74HC_HCT244
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2012. All rights reserved.
Product data sheet
Rev. 4 — 24 September 2012
3 of 18
NXP Semiconductors
74HC244; 74HCT244
Octal buffer/line driver; 3-state
6. Functional description
Table 3.
Input
nOE
L
L
H
[1]
Function table
[1]
Output
nAn
L
H
X
nYn
L
H
Z
H = HIGH voltage level; L = LOW voltage level; X = don’t care; Z = high-impedance OFF-state.
7. Limiting values
Table 4.
Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134). Voltages are referenced to GND (ground = 0 V).
Symbol
V
CC
I
IK
I
OK
I
O
I
CC
I
GND
T
stg
P
tot
Parameter
supply voltage
input clamping current
output clamping current
output current
supply current
ground current
storage temperature
total power dissipation
DIP20 package
SO20, SSOP20, TSSOP20 and
DHVQFN20 packages
[1]
[2]
For DIP20 package: P
tot
derates linearly with 12 mW/K above 70
C.
For SO20 packages: P
tot
derates linearly with 8 mW/K above 70
C.
For SSOP20 and TSSOP20 packages: P
tot
derates linearly with 5.5 mW/K above 60
C.
For DHVQFN20 packages: above 60
C,
P
tot
derates linearly with 4.5 mW/K.
[1]
[2]
Conditions
V
I
<
0.5
V or V
I
> V
CC
+ 0.5 V
V
O
<
0.5
V or V
O
> V
CC
+ 0.5 V
0.5
V < V
O
< V
CC
+ 0.5 V
Min
0.5
-
-
-
-
70
65
-
-
Max
+7
20
20
35
70
-
+150
750
500
Unit
V
mA
mA
mA
mA
mA
C
mW
mW
8. Recommended operating conditions
Table 5.
Symbol
74HC244
V
CC
V
I
V
O
t/V
supply voltage
input voltage
output voltage
input transition rise and fall rate V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
T
amb
ambient temperature
2.0
0
0
-
-
-
40
5.0
-
-
-
1.67
-
-
6.0
V
CC
V
CC
625
139
83
+125
V
V
V
ns/V
ns/V
ns/V
C
Recommended operating conditions
Parameter
Conditions
Min
Typ
Max
Unit
74HC_HCT244
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2012. All rights reserved.
Product data sheet
Rev. 4 — 24 September 2012
4 of 18
NXP Semiconductors
74HC244; 74HCT244
Octal buffer/line driver; 3-state
Table 5.
Symbol
74HCT244
V
CC
V
I
V
O
t/V
T
amb
Recommended operating conditions
…continued
Parameter
supply voltage
input voltage
output voltage
input transition rise and fall rate V
CC
= 4.5 V
ambient temperature
Conditions
Min
4.5
0
0
-
40
Typ
5.0
-
-
1.67
-
Max
5.5
V
CC
V
CC
139
+125
Unit
V
V
V
ns/V
C
9. Static characteristics
Table 6.
Static characteristics
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol Parameter
74HC244
V
IH
HIGH-level
input voltage
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
V
IL
LOW-level
input voltage
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
V
OH
HIGH-level
V
I
= V
IH
or V
IL
output voltage
I
O
=
20 A;
V
CC
= 2.0 V
I
O
=
20 A;
V
CC
= 4.5 V
I
O
=
20 A;
V
CC
= 6.0 V
I
O
=
6.0
mA; V
CC
= 4.5 V
I
O
=
7.8
mA; V
CC
= 6.0 V
V
OL
LOW-level
V
I
= V
IH
or V
IL
output voltage
I
O
= 20
A;
V
CC
= 2.0 V
I
O
= 20
A;
V
CC
= 4.5 V
I
O
= 20
A;
V
CC
= 6.0 V
I
O
= 6.0 mA; V
CC
= 4.5 V
I
O
= 7.8 mA; V
CC
= 6.0 V
I
I
I
OZ
input leakage
current
OFF-state
output current
V
I
= V
CC
or GND;
V
CC
= 6.0 V
per input pin; V
I
= V
IH
or V
IL
;
V
O
= V
CC
or GND;
other inputs at V
CC
or GND;
V
CC
= 6.0 V; I
O
= 0 A
1.5
3.15
4.2
-
-
-
1.9
4.4
5.9
1.2
2.4
3.2
0.8
2.1
2.8
2.0
4.5
6.0
-
-
-
0.5
1.35
1.8
-
-
-
-
-
0.1
0.1
0.1
0.26
0.26
0.1
0.5
1.5
3.15
4.2
-
-
-
1.9
4.4
5.9
3.84
5.34
-
-
-
-
-
-
-
-
-
-
0.5
1.35
1.8
-
-
-
-
-
0.1
0.1
0.1
0.33
0.33
1.0
5.0
1.5
3.15
4.2
-
-
-
1.9
4.4
5.9
3.7
5.2
-
-
-
-
-
-
-
-
-
-
0.5
1.35
1.8
-
-
-
-
-
0.1
0.1
0.1
0.4
0.4
1.0
10
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
A
A
Conditions
Min
25
C
Typ
Max
40 C
to +85
C 40 C
to +125
C
Unit
Min
Max
Min
Max
3.98 4.32
5.48 5.81
-
-
-
-
-
-
-
0
0
0
0.15
0.16
-
-
I
CC
C
I
supply current V
I
= V
CC
or GND; I
O
= 0 A;
V
CC
= 6.0 V
input
capacitance
-
-
-
3.5
8.0
-
-
-
80
-
-
-
160
-
A
pF
74HC_HCT244
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2012. All rights reserved.
Product data sheet
Rev. 4 — 24 September 2012
5 of 18