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IDT54/74FCT621T/AT
FAST CMOS OCTAL BUS TRANSCEIVER (OPEN DRAIN)
MILITARY AND COMMERCIAL TEMPERATURE RANGES
6.18
4
POWER SUPPLY CHARACTERISTICS
Symbol
Parameter
I
CC
Quiescent Power Supply Current
TTL Inputs HIGH
I
CCD
Dynamic Power Supply Current
(4)
Test Conditions
(1)
Min.
—
Typ.
(2)
0.5
Max.
2.0
Unit
mA
V
CC
= Max.
V
IN
= 3.4V
(3)
Vcc = Max.
Outputs Open
G
BA = GAB = GND or V
CC
One Input Toggling
50% Duty Cycle
Vcc = Max.
Outputs Open
G
BA = GAB = GND or V
CC
One Bit Toggling
at f
i
=10MHz
50% Duty Cycle
Vcc = Max.
Outputs Open
G
BA = GAB = GND or V
CC
Eight Bits Toggling
at f
i
= 2.5MHz
50% Duty Cycle
V
IN
= V
CC
V
IN
= GND
—
0.15
0.25
mA/MHz
I
C
Total Power Supply Current
(6,7)
V
IN
= V
CC
V
IN
= GND
—
1.5
3.5
mA
V
IN
= 3.4V
V
IN
= GND
—
1.8
4.5
V
IN
= V
CC
V
IN
= GND
—
3.0
6.0
(5)
V
IN
= 3.4V
V
IN
= GND
—
5.0
14.0
(5)
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
CP
/2 + f
i
N
i
)
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 Output Transition Pair (HLH or LHL)
f
CP
= Clock Frequency for Register Devices (Zero for Non-Register Devices)
f
i
= Input Frequency
N
i
= Number of Inputs at f
i
All currents are in milliamps and all frequencies are in megahertz.
7. This test is performed with outputs tied to GND through a pull-down resistor.
2538 tbl 06
IDT54/74FCT621T
Com’l.
Min.
(2)
Max.
IDT54/74FCT621AT
Com’l.
Min.
(2)
Max. Min.
(2)
Mil.
Mil.
Symbol
Parameter
Condition
(1)
Min.
(2)
Max.
Max.
Unit
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
Propagation Delay A to B
C
L
= 50pF
R
L
= 500
5.5
1.5
5.5
1.5
5.5
1.5
5.5
1.5
13.0
8.5
12.5
8.0
14.0
8.5
14.0
8.0
5.5
1.5
5.5
1.5
5.5
1.5
5.5
1.5
13.5
9.5
13.0
9.0
14.5
9.5
14.5
9.0
5.5
1.5
5.5
1.5
5.5
1.5
5.5
1.5
12.0
6.8
12.0
6.4
13.0
6.8
13.0
6.4
5.5
1.5
5.5
1.5
5.5
1.5
5.5
1.5
12.5
7.6
12.5
7.2
13.5
7.6
13.5
7.2
ns
Propagation Delay B to A
ns
Propagation Delay
G
BA to A
ns
Propagation Delay GAB to B
ns
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
NOTES:
1. See test circuit and waveforms.
2. Minimum limits are guaranteed but not tested on Propagation Delays.
2538 tbl 07