IDT54/74FCT138T/AT/CT
FAST CMOS 1-OF-8 DECODER WITH ENABLE
MILITARY AND INDUSTRIAL TEMPERATURE RANGES
POWER SUPPLY CHARACTERISTICS
Symbol
∆ICC
ICCD
Parameter
Quiescent Power Supply Current
TTL Inputs HIGH
Dynamic Power Supply
Current(4)
IC
Total Power Supply Current(5)
Test Conditions(1)
VCC = Max.
VIN = 3.4V(3)
VCC = Max.
Outputs Open
One Input Toggling
50% Duty Cycle
VIN = VCC
VIN = GND
VCC = Max.
Outputs Open
Toggle E1, E2, or E3
VIN = VCC
VIN = GND
50% Duty Cycle
fo = 10MHz
One Input and
VIN = 3.4V
VIN = GND
One Output Toggling
Min. Typ.(2) Max.
Unit
—
0.5
2
mA
—
0.15
0.3
mA/
MHz
—
1.5
4
mA
—
1.8
5
NOTES:
1. For conditions shown as Min. or Max., use appropriate value specified under Electrical Characteristics for the applicable device type.
2. Typical values are at VCC = 5.0V, +25°C ambient.
3. Per TTL driven input; (VIN = 3.4V). All other inputs at VCC or GND.
4. This parameter is not directly testable, but is derived for use in Total Power Supply Calculations.
5. IC = IQUIESCENT + IINPUTS + IDYNAMIC
IC = ICC + ∆ICC DHNT + ICCD (fONO)
ICC = Quiescent Current
∆ICC = Power Supply Current for a TTL High Input (VIN = 3.4V)
DH = Duty Cycle for TTL Inputs High
NT = Number of TTL Inputs at DH
ICCD = Dynamic Current caused by an Input Transition Pair (HLH or LHL)
fO = Output Frequency
NO = Number of Outputs at fO
All currents are in milliamps and all frequencies are in megahertz.
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
54FCT138T
Mil.
54/74FCT138AT
Ind.
Mil.
54/74FCT138CT
Ind.
Mil.
Symbol
Parameter
Condition(1)
Min.(2)
Max. Min.(2) Max. Min.(2) Max. Min.(2) Max. Min.(2) Max. Unit
tPLH
Propagation Delay
CL = 50pF
tPHL
Ax to Ox
RL = 500Ω
tPLH
Propagation Delay
tPHL
E1 or E2 to Ox
tPLH
Propagation Delay
tPHL
E3 to Ox
1.5
12
1.5 5.8
1.5 7.8
1.5
5.1
1.5 6 ns
1.5
12.5
1.5 5.9
1.5
8
1.5
5.2
1.5 6.1 ns
1.5
12.5
1.5 5.9
1.5
8
1.5
5.2
1.5 6.1 ns
NOTES:
1. See test circuit and waveforms.
2. Minimum limits are guaranteed but not tested on Propagation Delays.
4