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6.3
4
IDT54/74FCT138T/AT/CT
FAST CMOS 1-OF-8 DECODER-WITH ENABLE
MILITARY AND COMMERCIAL TEMPERATURE RANGES
POWER SUPPLY CHARACTERISTICS
NOTES:
1. For conditions shown as Max. or Min., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at V
CC
= 5.0V, +25
°
C ambient.
3. Per TTL driven input (V
IN
= 3.4V). All other inputs at V
CC
or GND.
4. This parameter is not directly testable, but is derived for use in Total Power Supply Calculations.
5. Values for these conditions are examples of the I
CC
formula. These limits are guaranteed but not tested.
6. I
C
= I
QUIESCENT
+ I
INPUTS
+ I
DYNAMIC
I
C
= I
CC
+
I
CC
D
H
N
T
+ I
CCD
(f
o
N
o
)
I
CC
= Quiescent Current
I
CC
= Power Supply Current for a TTL High Input (V
IN
= 3.4V)
D
H
= Duty Cycle for TTL Inputs High
N
T
= Number of TTL Inputs at D
H
I
CCD
= Dynamic Current Caused by an Input Transition Pair (HLH or LHL)
f
o
= Output Frequency
N
o
= Number of Outputs at f
o
All currents are in milliamps and all frequencies are in megahertz.
2570 tbl 06
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
NOTES:
1. See test circuit and waveforms.
2. Minimum limits are guaranteed but not tested on Propagation Delays.
2570 tbl 07
Symbol
I
CC
Parameter
Test Conditions
(1)
Min.
—
Typ.
(2)
0.5
Max.
2.0
Unit
mA
Quiescent Power Supply Current
TTL Inputs HIGH
Dynamic Power Supply Current
(4)
V
CC
= Max.
V
IN
= 3.4V
(3)
V
CC
= Max.
Outputs Open
One Bit Toggling
50% Duty Cycle
V
CC
= Max.
Outputs Open
Toggle
E
1
,
E
2
or E
3
50% Duty Cycle
fo = 10MHz
One Input and
One Output Toggling
I
CCD
V
IN
= V
CC
V
IN
= GND
—
0.15
0.3
mA/
MHz
I
C
Total Power Supply Current
(6)
V
IN
= V
CC
V
IN
= GND
—
1.5
4.0
mA
V
IN
= 3.4V
V
IN
= GND
—
1.8
5.0
FCT138T
FCT138AT
FCT138CT
Com'l.
Mil.
Com'l.
Mil.
Com'l.
Mil.
Symbol
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
Parameter
Condition
(1)
C
L
= 50pF
R
L
= 500
Min.
(2)
1.5
Max.
9.0
Min.
(2)
1.5
Max. Min.
(2)
12.0
Max.
5.8
Min.
(2)
1.5
Max.
7.8
Min.
(2)
1.5
Max.
5.1
Min.
(2)
1.5
Max.
6.0
Unit
ns
Propagation Delay
A
n
to
O
n
Propagation Delay
E
1
or
E
2
to
O
n
Propagation Delay
E
3
to
O
n
1.5
1.5
9.0
1.5
12.5
1.5
5.9
1.5
8.0
1.5
5.2
1.5
6.1
ns
1.5
9.0
1.5
12.5
1.5
5.9
1.5
8.0
1.5
5.2
1.5
6.1
ns