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74AC821 • 74ACT821
Absolute Maximum Ratings(Note 1) Recommended Operating
Conditions
Note 1: Absolute maximum ratings are those values beyond which damage
to the device may occur. The databook specifications should be met, with-
out exception, to ensure that the system design is reliable over its power
supply, temperature, and output/input loading variables. Fairchild does not
recommend operation of FACT circuits outside databook specifications.
DC Electrical Characteristics for AC
Note 2: All outputs loaded; thresholds on input associated with output under test.
Note 3: Maximum test duration 2.0 ms, one output loaded at a time.
Note 4: I
IN
and I
CC
@ 3.0V are guaranteed to be less than or equal to the respective limit @ 5.5V V
CC
.
Supply Voltage (V
CC
) − 0.5V to + 7.0V
DC Input Diode Current (I
IK
)
V
I
= − 0.5V − 20 mA
V
I
= V
CC
+ 0.5V + 20 mA
DC Input Voltage (V
I
) − 0.5V to V
CC
+ 0.5V
DC Output Diode Current (I
OK
)
V
O
= −0.5V − 20 mA
V
O
= V
CC
+ 0.5V + 20 mA
DC Output Voltage (V
O
) − 0.5V to V
CC
+ 0.5V
DC Output Source
or Sink Current (I
O
) ± 50 mA
DC V
CC
or Ground Current
per Output Pin (I
CC
or I
GND
) ± 50 mA
Storage Temperature (T
STG
) − 65°C to + 150°C
Junction Temperature (T
J
)
PDIP 140
°C
Supply Voltage (V
CC
)
AC 2.0V to 6.0V
ACT 4.5V to 5.5V
Input Voltage (V
I
)0V to V
CC
Output Voltage (V
O
)0V to V
CC
Operating Temperature (T
A
) − 40°C to + 85°C
Minimum Input Edge Rate (
∆V/∆t)
AC Devices
V
IN
from 30% to 70% of V
CC
V
CC
@ 3.3V, 4.5V, 5.5V 125 mV/ns
Minimum Input Edge Rate (
∆V/∆t)
ACT Devices
V
IN
from 0.8V to 2.0V
V
CC
@ 4.5V, 5.5V 125 mV/ns
Symbol Parameter
V
CC
T
A
= +25°CT
A
= −40°C to +85°C
Units Conditions
(V) Typ Guaranteed Limits
V
IH
Minimum HIGH Level 3.0 1.5 2.1 2.1 V
OUT
= 0.1V
Input Voltage 4.5 2.25 3.15 3.15 V or V
CC
− 0.1V
5.5 2.75 3.85 3.85
V
IL
Maximum LOW Level 3.0 1.5 0.9 0.9 V
OUT
= 0.1V
Input Voltage 4.5 2.25 1.35 1.35 V or V
CC
− 0.1V
5.5 2.75 1.65 1.65
V
OH
Minimum HIGH Level 3.0 2.99 2.9 2.9
Output Voltage 4.5 4.49 4.4 4.4 V I
OUT
= − 50 µA
5.5 5.49 5.4 5.4
V
IN
= V
IL
or V
IH
3.0 2.56 2.46 I
OH
= − 12 mA
4.5 3.86 3.76 V I
OH
= − 24 mA
5.5 4.86 4.76 I
OH
= − 24 mA (Note 2)
V
OL
Maximum LOW Level 3.0 0.002 0.1 0.1
Output Voltage 4.5 0.001 0.1 0.1 V I
OUT
= 50 µA
5.5 0.001 0.1 0.1
V
IN
= V
IL
or V
IH
3.0 0.36 0.44 I
OL
= 12 mA
4.5 0.36 0.44 V I
OL
= 24 mA
5.5 0.36 0.44 I
OL
= 24 mA (Note 2)
I
IN
(Note 4) Maximum Input Leakage Current 5.5 ± 0.1 ± 1.0 µAV
I
= V
CC
, GND
I
OZ
Maximum 3-STATE Current V
I
(OE) = V
IL
, V
IH
5.5 ±0.5 ±5.0 µAV
I
= V
CC
, GND
V
O
= V
CC
, GND
I
OLD
Minimum Dynamic 5.5 75 mA V
OLD
= 1.65V Max
I
OHD
Output Current (Note 3) 5.5 −75 mA V
OHD
= 3.85V Min
I
CC
(Note 4) Maximum Quiescent Supply Current 5.5 8.0 80.0 µAV
IN
= V
CC
or GND
