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DM74AS157 • DM74AS158
DM74AS157 Switching Characteristics
over recommended operating free air temperature range
DM74AS158 Switching Characteristics
over recommended operating free air temperature range
Symbol Parameter Conditions
From To
Min Max Units
(Input) (Output)
t
PLH
Propagation Delay Time, V
CC
= 4.5V to 5.5V,
Data Y 1 6 ns
LOW-to-HIGH Level Output C
L
= 50 pF,
t
PHL
Propagation Delay Time, R
L
= 500Ω
Data Y 1 5.5 ns
HIGH-to-LOW Level Output
t
PLH
Propagation Delay Time,
STROBE Y210.5ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time,
STROBE Y27.5ns
HIGH-to-LOW Level Output
t
PLH
Propagation Delay Time,
Select Y 2 11 ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time,
Select Y 2 10 ns
HIGH-to-LOW Level Output
Symbol Parameter Conditions
From To
Min Max Units
(Input) (Output)
t
PLH
Propagation Delay Time, V
CC
= 4.5V to 5.5V,
Data Y 1 5 ns
LOW-to-HIGH Level Output C
L
= 50 pF,
t
PHL
Propagation Delay Time, R
L
= 500Ω
Data Y 1 4.5 ns
HIGH-to-LOW Level Output
t
PLH
Propagation Delay Time,
STROBE Y26.5ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time,
STROBE Y 2 10 ns
HIGH-to-LOW Level Output
t
PLH
Propagation Delay Time,
Select Y 2 9.5 ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time,
Select Y 2 10.5 ns
HIGH-to-LOW Level Output
