Fairchild DM74ALS521 8-bit comparator Datasheet

Revised April 2000
DM74ALS520 • DM74ALS521
8-Bit Comparator
General Description
Features
These comparators perform an “equal to” comparison of
two 8-bit words with provision for expansion or external
enabling. The matching of the two 8-bit input plus a logic
LOW on the EN input produces the output A = B on the
DM74ALS520 and DM74ALS521. The DM74ALS520 and
DM74ALS521 have totem pole outputs for wire AND cascading. Additionally, the DM74ALS520 is provided with B
input pull up termination resistors for analog or switch data.
■ Switching specifications at 50 pF
■ Switching specifications guaranteed over full temperature and VCC range
■ Advanced oxide-isolated, ion-implanted Schottky TTL
process
■ Functionally and pin for pin compatible with LS family
counterpart
■ Improved output transient handling capability
Ordering Code:
Ordering Code
Package Number
DM74ALS520WM
M20B
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
Package Description
DM74ALS520N
N20A
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
DM74ALS521WM
M20B
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
SM74ALS521N
N20A
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
Connection Diagram
Function Table
Inputs
Output
A=B
EN
Data
L
A=B
L
L
A≠B
H
H
X
H
H = HIGH Logic Level
L = LOW Logic Level
X = Don't Care
© 2000 Fairchild Semiconductor Corporation
DS006114
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DM74ALS520 • DM74ALS521 8-Bit Comparator
September 1986
DM74ALS520 • DM74ALS521
Logic Diagram
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2
Supply Voltage
7V
Input Voltage
7V
0°C to +70°C
Operating Free Air Temperature Range
Note 1: The “Absolute Maximum Ratings” are those values beyond which
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommended Operating Conditions” table will define the conditions
for actual device operation.
−65°C to +150°C
Storage Temperature Range
Typical θJA
N Package
62.0°C/W
M Package
82.0°C/W
Recommended Operating Conditions
Symbol
Parameter
Min
Nom
Max
4.5
5
5.5
Units
VCC
Supply Voltage
VIH
HIGH Level Input Voltage
VIL
LOW Level Input Voltage
0.8
V
IOH
HIGH Level Output Current
−2.6
mA
IOL
LOW Level Output Current
24
mA
TA
Free Air Operating Temperature
70
°C
V
2
V
0
Electrical Characteristics
over recommended operating free air temperature range. All typical values are measured at VCC = 5V, TA = 25°C.
Symbol
Parameter
Conditions
VIK
Input Clamp Voltage
VCC = 4.5V, II = −18 mA
VOH
HIGH Level
VCC = 4.5V to 5.5V
Output Voltage
IOH = −400 µA
Min
Typ
Max
Units
−1.5
V
VCC − 2
VCC = 4.5V
V
2.4
IOH = Max
VOL
LOW Level Output Voltage
VCC = 4.5V
IOL = 24 mA
II
Max HIGH
VCC = 5.5V
VIH = 5.5V
Input Current
3.2
V
0.35
B Input DM74ALS520
0.5
V
0.1
mA
VIH = 7V, All Others
HIGH Level
VCC = 5.5V,
All Others
Input Current
VIH = 2.7V
B Input DM74ALS520
−200
Low Level Input
VCC = 5.5V,
B Input DM74ALS520
−0.6
mA
Current
VIL = 0.4V
All Others
−0.1
mA
IO
Output Drive Current
VCC = 5.5V
VO = 2.25V
−112
mA
ICC
Supply Current
VCC = 5.5V (Note 2)
19
mA
IIH
IIL
20
−30
12
µA
Note 2: ICC is measured with EN grounded, A and B inputs at 4.5V and outputs OPEN.
Switching Characteristics
over recommended operating free air temperature range
Symbol
tPLH
tPHL
Parameter
Conditions
Output
Min
Max
Units
A=B
3
12
ns
A=B
5
20
ns
EN
A=B
2
12
ns
EN
A=B
5
22
ns
VCC = 4.5V to 5.5V
LOW-to-HIGH Level Output
CL = 50 pF
Data
Propagation Delay Time
RL = 500Ω
A or B
A or B
Data
Propagation Delay Time
LOW-to-HIGH Level Output
tPHL
To
Input
Propagation Delay Time
HIGH-to-LOW Level Output
tPLH
From
Propagation Delay Time
HIGH-to-LOW Level Output
3
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DM74ALS520 • DM74ALS521
Absolute Maximum Ratings(Note 1)
DM74ALS520 • DM74ALS521
Physical Dimensions inches (millimeters) unless otherwise noted
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
Package Number M20B
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4
DM74ALS520 • DM74ALS521 8-Bit Comparator
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Package Number N20A
Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:
2. A critical component in any component of a life support
device or system whose failure to perform can be reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the
body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with
instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the
user.
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