NXP Semiconductors
74HC244; 74HCT244
Octal buffer/line driver; 3-state
Table 7.
Dynamic characteristics
…continued
GND = 0 V; for load circuit see
Figure 8.
Symbol Parameter
Conditions
Min
t
en
enable time
nOE to nYn; see
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
t
dis
disable time
nOE to nYn or see
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
t
t
transition time
see
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
C
PD
power dissipation
capacitance
per buffer; V
I
= GND to V
CC
25
C
Typ
Max
40 C
to +125
C
Unit
Max
(85
C)
190
38
33
190
38
33
75
15
13
-
Max
(125
C)
225
45
38
225
45
38
90
18
15
-
ns
ns
ns
ns
ns
ns
ns
ns
ns
pF
-
-
-
-
-
-
-
-
-
-
36
13
10
39
14
11
14
5
4
35
150
30
26
150
30
26
60
12
10
-
74HCT244
t
pd
propagation delay nAn to nYn;
see
V
CC
= 4.5 V
V
CC
= 5.0 V; C
L
= 15 pF
t
en
t
dis
t
t
C
PD
enable time
disable time
transition time
power dissipation
capacitance
nOE to nYn; V
CC
= 4.5 V; see
nOE to nYn; V
CC
= 4.5 V; see
V
CC
= 4.5 V; see
per buffer;
V
I
= GND to V
CC
1.5 V
-
-
-
-
-
-
13
11
15
15
5
35
22
-
30
25
12
-
28
-
38
31
15
-
33
-
45
38
18
-
ns
ns
ns
ns
ns
pF
[1]
[2]
[3]
[4]
[5]
t
pd
is the same as t
PHL
and t
PLH
.
t
en
is the same as t
PZH
and t
PZL
.
t
dis
is the same as t
PHZ
and t
PLZ
.
t
t
is the same as t
THL
and t
TLH
.
C
PD
is used to determine the dynamic power dissipation (P
D
in
W):
P
D
= C
PD
V
CC2
f
i
N +
(C
L
V
CC2
f
o
) where:
f
i
= input frequency in MHz;
f
o
= output frequency in MHz;
C
L
= output load capacitance in pF;
V
CC
= supply voltage in V;
N = number of inputs switching;
(C
L
V
CC2
f
o
) = sum of outputs.
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
7 of 18
PHILIPS [ NXP SEMICONDUCTORS ]
