DATA SHEET
Product specification
File under Integrated Circuits, IC06
December 1990
INTEGRATED CIRCUITS
74HC/HCT244
Octal buffer/line driver; 3-state
For a complete data sheet, please also download:
The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications
The IC06 74HC/HCT/HCU/HCMOS Logic Package Information
The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines
December 1990
2
Philips Semiconductors
Product specification
Octal buffer/line driver; 3-state
74HC/HCT244
FEATURES
Output capability: bus driver
I
CC
category: MSI
GENERAL DESCRIPTION
The 74HC/HCT244 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
The 74HC/HCT244 are octal non-inverting buffer/line
drivers with 3-state outputs. The 3-state outputs are
controlled by the output enable inputs 1OE and 2OE.
A HIGH on nOE causes the outputs to assume a high
impedance OFF-state. The "244" is identical to the "240"
but has non-inverting outputs.
QUICK REFERENCE DATA
GND = 0 V; T
amb
= 25
C; t
r
= t
f
= 6 ns
Notes
1. C
PD
is used to determine the dynamic power dissipation (P
D
in
W):
P
D
= C
PD
V
CC
2
f
i
+
(C
L
V
CC
2
f
o
) where:
f
i
= input frequency in MHz
f
o
= output frequency in MHz
(C
L
V
CC
2
f
o
) = sum of outputs
C
L
= output load capacitance in pF
V
CC
= supply voltage in V
2. For HC the condition is V
I
= GND to V
CC
For HCT the condition is V
I
= GND to V
CC
-
1.5 V
ORDERING INFORMATION
See
"74HC/HCT/HCU/HCMOS Logic Package Information"
.
SYMBOL
PARAMETER
CONDITIONS
TYPICAL
UNIT
HC
HCT
t
PHL
/ t
PLH
propagation delay
1A
n
to 1Y
n
;
2A
n
to 2Y
n
C
L
= 15 pF; V
CC
= 5 V
9
11
ns
C
I
input capacitance
3.5
3.5
pF
C
PD
power dissipation capacitance per buffer
notes 1 and 2
35
35
pF
December 1990
3
Philips Semiconductors
Product specification
Octal buffer/line driver; 3-state
74HC/HCT244
PIN DESCRIPTION
PIN NO.
SYMBOL
NAME AND FUNCTION
1
1OE
output enable input (active LOW)
2, 4, 6, 8
1A
0
to 1A
3
data inputs
3, 5, 7, 9
2Y
0
to 2Y
3
bus outputs
10
GND
ground (0 V)
17, 15, 13, 11
2A
0
to 2A
3
data inputs
18, 16, 14, 12
1Y
0
to 1Y
3
bus outputs
19
2OE
output enable input (active LOW)
20
V
CC
positive supply voltage
Fig.1 Pin configuration.
Fig.2 Logic symbol.
Fig.3 IEC logic symbol.
December 1990
4
Philips Semiconductors
Product specification
Octal buffer/line driver; 3-state
74HC/HCT244
Fig.4 Functional diagram.
FUNCTION TABLE
Note
1. H = HIGH voltage level
L = LOW voltage level
X = don't care
Z = high impedance OFF-state
INPUTS
OUTPUT
nOE
nA
n
nY
n
L
L
H
L
H
X
L
H
Z
December 1990
5
Philips Semiconductors
Product specification
Octal buffer/line driver; 3-state
74HC/HCT244
DC CHARACTERISTICS FOR 74HC
For the DC characteristics see
"74HC/HCT/HCU/HCMOS Logic Family Specifications"
.
Output capability: bus driver
I
CC
category: MSI
AC CHARACTERISTICS FOR 74HC
GND = 0 V; t
r
= t
f
= 6 ns; C
L
= 50 pF
SYMBOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HC
V
CC
(V)
WAVEFORMS
+
25
-
40 to
+
85
-
40 to
+
125
min.
typ.
max. min. max. min.
max.
t
PHL
/ t
PLH
propagation delay
1A
n
to 1Y
n;
2A
n
to 2Y
n
30
11
9
110
22
19
145
28
24
165
33
28
ns
2.0
4.5
6.0
Fig.5
t
PZH
/ t
PZL
3-state output enable time
1OE to 1Y
n;
2OE to 2Y
n
36
13
10
150
30
26
190
38
33
225
45
38
ns
2.0
4.5
6.0
Fig.6
t
PHZ
/ t
PLZ
3-state output disable time
1OE to 1Y
n;
2OE to 2Y
n
39
14
11
150
30
26
190
38
33
225
45
38
ns
2.0
4.5
6.0
Fig.6
t
THL
/ t
TLH
output transition time
14
5
4
60
12
10
75
15
13
90
18
15
ns
2.0
4.5
6.0
Fig.5
December 1990
6
Philips Semiconductors
Product specification
Octal buffer/line driver; 3-state
74HC/HCT244
DC CHARACTERISTICS FOR 74HCT
For the DC characteristics see
"74HC/HCT/HCU/HCMOS Logic Family Specifications"
.
Output capability: bus driver
I
CC
category: MSI
Note to HCT types
The value of additional quiescent supply current (
I
CC
) for a unit load of 1 is given in the family specifications.
To determine
I
CC
per input, multiply this value by the unit load coefficient shown in the table below.
AC CHARACTERISTICS FOR 74HCT
GND = 0 V; t
r
= t
f
= 6 ns; C
L
= 50 pF
INPUT
UNIT LOAD COEFFICIENT
1A
n
2A
n
1OE
2OE
0.70
0.70
0.70
0.70
SYMBOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HCT
V
CC
(V)
WAVEFORMS
+
25
-
40 to
+
85
-
40 to
+
125
min.
typ.
max. min. max. min.
max.
t
PHL
/ t
PLH
propagation delay
1A
n
to 1Y
n;
2A
n
to 2Y
n
13
22
28
33
ns
4.5
Fig.5
t
PZH
/ t
PZL
3-state output enable time
1OE to 1Y
n;
2OE to 2Y
n
15
30
38
45
ns
4.5
Fig.6
t
PHZ
/ t
PLZ
3-state output disable time
1OE to 1Y
n;
2OE to 2Y
n
15
25
31
38
ns
4.5
Fig.6
t
THL
/ t
TLH
output transition time
5
12
15
18
ns
4.5
Fig.5
December 1990
7
Philips Semiconductors
Product specification
Octal buffer/line driver; 3-state
74HC/HCT244
AC WAVEFORMS
PACKAGE OUTLINES
See
"74HC/HCT/HCU/HCMOS Logic Package Outlines"
.
Fig.5
Waveforms showing the input (1A
n
, 2A
n
) to output (1Y
n
, 2Y
n
) propagation delays and the output transition
times.
(1) HC : V
M
= 50%; V
I
= GND to V
CC
.
HCT : V
M
= 1.3 V; V
I
= GND to 3 V.
Fig.6 Waveforms showing the 3-state enable and disable times.
(1) HC : V
M
= 50%; V
I
= GND to V
CC
.
HCT : V
M
= 1.3 V; V
I
= GND to 3 V.
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