Datasheet

www.fairchildsemi.com 4
MM74HC138
AC Electrical Characteristics
V
CC
= 5V, T
A
= 25°C, C
L
= 15 pF, t
r
= t
f
= 6 ns
AC Electrical Characteristics
C
L
= 50 pF, t
r
= t
f
= 6 ns (unless otherwise specified)
Note 6: C
PD
determines the no load dynamic power consumption, P
D
= C
PD
V
CC
2
f + I
CC
V
CC
, and the no load dynamic current consumption,
I
S
= C
PD
V
CC
f + I
CC
.
Symbol Parameter Conditions Typ
Guaranteed
Units
Limit
t
PLH
Maximum Propagation 18 25 ns
Delay, Binary Select to any Output
t
PHL
Maximum Propagation 28 35 ns
Delay, Binary Select to any Output
t
PHL
, t
PLH
Maximum Propagation 18 25 ns
Delay, G1 to any Output
t
PHL
Maximum Propagation 23 30 ns
Delay G2A or G2B to
Output
t
PLH
Maximum Propagation 18 25 ns
Delay G2A or G2B to Output
Symbol Parameter Conditions
V
CC
T
A
= 25°CT
A
= −40 to 85°C
Units
Typ Guaranteed Limits
t
PLH
Maximum Propagation 2.0V 75 150 189 ns
Delay Binary Select to 4.5V 15 30 38 ns
any Output LOW-to-HIGH 6.0V 13 26 32 ns
t
PHL
Maximum Propagation 2.0V 100 200 252 ns
Delay Binary Select to any 4.5V 20 40 50 ns
Output HIGH-to-LOW 6.0V 17 34 43 ns
t
PHL
, t
PLH
Maximum Propagation 2.0V 75 150 189 ns
Delay G1 to any 4.5V 15 30 38 ns
Output 6.0V 13 26 32 ns
t
PHL
Maximum Propagation 2.0V 82 175 221 ns
Delay G2A or G2B to
4.5V 28 35 44 ns
Output 6.0V 22 30 37 ns
t
PLH
Maximum Propagation 2.0V 75 150 189 ns
Delay G2A or G2B to
4.5V 15 30 38 ns
Output 6.0V 13 26 32 ns
t
TLH
, t
THL
Output Rise and 2.0V 30 75 95 ns
Fall Time 4.5V 8 15 19 ns
6.0V 7 13 16 ns
C
IN
Maximum Input 3 10 10 pF
Capacitance
C
PD
Power Dissipation (Note 6) 75 pF
Capacitance