Datasheet

www.fairchildsemi.com 4
74VHC244
AC Electrical Characteristics
Note 4: Parameter guaranteed by design. t
OSLH
|t
PLHmax
t
PLHmin
|; t
OSHL
|t
PHLmax
t
PHLmin
|.
Note 5: 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.) C
PD
* V
CC
* f
IN
I
CC
/8 (per bit).
Symbol Parameter
V
CC
T
A
25 CT
A
40 C to 85 C
Units Conditions
(V) Min Typ Max Min Max
t
PLH
Propagation Delay 3.3 0.3 5.8 8.4 1.0 10.0
ns
C
L
15 pF
t
PHL
Time 8.3 11.9 1.0 13.5 C
L
50 pF
5.0 0.5 3.9 5.5 1.0 6.5
ns
C
L
15 pF
5.4 7.5 1.0 8.5 C
L
50 pF
t
PZL
3-STATE Output 3.3 0.3 6.6 10.6 1.0 12.5
ns
R
L
1 k
C
L
15 pF
t
PZH
Enable Time 9.1 14.1 1.0 16.0 C
L
50 pF
5.0 0.5
4.7 7.3 1.0 8.5
ns
C
L
15 pF
6.2 9.3 1.0 10.5 C
L
50 pF
t
PLZ
3-STATE Output 3.3 0.3 10.3 14.0 1.0 16.0
ns R
L
1 k
C
L
50 pF
t
PHZ
Disable Time 5.0 0.5 6.7 9.2 1.0 10.5 C
L
50 pF
t
OSLH
Output to Output 3.3 0.3 1.5 1.5
ns (Note 4)
C
L
50 pF
t
OSHL
Skew 5.0 0.5 1.0 1.0 C
L
50 pF
C
IN
Input Capacitance 4 10 10 pF V
CC
Open
C
OUT
Output Capacitance 6 pF V
CC
5.0V
C
PD
Power Dissipation Capacitance 19 pF (Note 5)