Datasheet

5
Switching Specifications Input t
r
, t
f
= 6ns
PARAMETER SYMBOL
TEST
CONDITIONS V
CC
(V)
25
o
C
-40
o
C TO
85
o
C
-55
o
C TO
125
o
C
UNITSMIN TYP MAX MIN MAX MIN MAX
HC TYPES
Propagation Delay t
PLH,
t
PHL
C
L
= 50pF 2 - - 245 - 305 - 370 ns
Select to Outputs 4.5 - - 49 - 61 - 74 ns
C
L
=15pF 5 - 21 - - - - - ns
C
L
= 50pF 6 - - 42 - 52 - 63 ns
Data to Outputs t
PLH,
t
PHL
C
L
= 50pF 2 - - 175 - 220 - 265 ns
4.5 - - 35 - 44 - 53 ns
C
L
=15pF 5 - 12 - - - - - ns
C
L
= 50pF 6 - - 30 - 37 - 45 ns
Enable to High Z and Enable
from High Z
t
PLH,
t
PHL
C
L
= 50pF 2 - - 140 - 175 - 210 ns
4.5 - - 28 - 35 - 42 ns
C
L
=15pF 5 - 11 - - - - - ns
C
L
= 50pF 6 - - 24 - 30 - 36 ns
Output Transition Time t
TLH
, t
THL
C
L
= 50pF 2 - - 75 - 95 - 110 ns
4.5 - - 15 - 19 - 22 ns
6 - - 13 - 16 - 19 ns
Input Capacitance C
IN
- - - - 10 - 10 - 10 pF
Three-State Output
Capacitance
CO - - - - 15 - 15 - 15 pF
Power Dissipation Capacitance
(Notes 3, 4)
C
PD
-5-60-----pF
HCT TYPES
Propagation Delay t
PLH
, t
PHL
Select to Outputs C
L
= 50pF 4.5 - - 42 - 53 - 63 ns
C
L
=15pF 5 - 18 - - - - ns
Data to Outputs t
PLH
, t
PHL
C
L
= 50pF 4.5 - - 35 - 44 - 53 ns
C
L
=15pF 5 - 12 - - - - - ns
Enable to High Z and Enable
from High Z
t
PLH
, t
PHL
C
L
= 50pF 4.5 - 30 - 38 - 45 ns
C
L
=15pF 5 - 12 - - - - - ns
Output Transition Time t
TLH
, t
THL
C
L
= 50pF 4.5 - - 15 - 19 - 22 ns
Input Capacitance C
IN
- - - - 10 - 10 - 10 pF
Power Dissipation Capacitance
(Notes 3, 4)
C
PD
- 5 60-----pF
NOTES:
3. C
PD
is used to determine the dynamic power consumption, per package.
4. P
D
= V
CC
2
f
i
(C
PD
+ C
L
) where f
i
= input frequency, C
L
= output load capacitance, V
CC
= supply voltage.
CD54HC251, CD74HC251, CD54HCT251, CD74HCT251