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MILITARY AND COMMERCIAL TEMPERATURE RANGES
4
IDT54/74FCT821/A/B
HIGH PERFORMANCE CMOS BUS INTERFACE REGISTER
POWER SUPPLY CHARACTERISTICS
V
LC
= 0.2V, V
HC
= V
CC
- 0.2V
Symbol
Parameter
Test Conditions
(1)
Min.
Typ.
(2)
Max.
Unit
I
CC
Quiescent Power Supply Current
V
CC
= Max.
V
IN
≥
V
HC
; V
IN
≤
V
LC
V
CC
= Max.
V
IN
= 3.4V
(3)
V
CC
= Max.
Outputs Open
OE
= GND
One Input Toggling
50% Duty Cycle
V
CC
= Max.
Outputs Open
f
CP
= 10MHz
50% Duty Cycle
OE
= GND
One Bit Toggling
at fi = 5MHz
50% Duty Cycle
V
CC
= Max.
Outputs Open
f
CP
= 10MHz
50% Duty Cycle
OE
= GND
Eight Bits Toggling
at fi = 2.5MHz
50% Duty Cycle
—
0.2
1.5
mA
I
CC
Quiescent Power Supply Current
TTL Inputs HIGH
Dynamc Power Supply
Current
(4)
—
0.5
2
mA
I
CCD
V
IN
≥
V
HC
V
IN
≤
V
LC
—
0.15
0.25
mA/
MHz
I
C
Total Power Supply Current
(6)
V
IN
≥
V
HC
V
IN
≤
V
LC
—
1.7
4
mA
V
IN
= 3.4V
V
IN
= GND
—
2.2
6
V
IN
≥
V
HC
V
IN
≤
V
LC
—
4
7.8
(5)
V
IN
= 3.4V
V
IN
= GND
—
6.2
16.8
(5)
NOTES:
1. For conditions shown as Mn. or Max., 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
I
CC
formula. These limts 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
= Dynamc Current caused by an Input Transition Pair (HLH or LHL)
f
CP
= Clock Frequency for Register Devices (Zero for Non-Register Devices)
f
i
= Output Frequency
N
i
= Number of Outputs at f
i
All currents are in mlliamps and all frequencies are in megahertz.