Freelance Electronics Components Distributor
Closed Dec 25th-26th
800-300-1968
We Stock Hard to Find Parts

DM74ALS520N

Part # DM74ALS520N
Description IC COMPARATOR IDENTITY 8B 20DIP
Category IC
Availability In Stock
Qty 3
Qty Price
1 + $0.45023
Manufacturer Available Qty
National Semiconductor Corp
  • Shipping Freelance Stock: 3
    Ships Immediately



Technical Document


DISCLAIMER: The information provided herein is solely for informational purposes. Customers must be aware of the suitability of this product for their application, and consider that variable factors such as Manufacturer, Product Category, Date Codes, Pictures and Descriptions may differ from available inventory.

© 2000 Fairchild Semiconductor Corporation DS006114 www.fairchildsemi.com
September 1986
Revised April 2000
DM74ALS520 • DM74ALS521 8-Bit Comparator
DM74ALS520 DM74ALS521
8-Bit Comparator
General Description
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 cas-
cading. Additionally, the DM74ALS520 is provided with B
input pull up termination resistors for analog or switch data.
Features
Switching specifications at 50 pF
Switching specifications guaranteed over full tempera-
ture and V
CC
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:
Devices also available in Tape and Reel. Specify by appending the suffix letter X to the ordering code.
Connection Diagram Function Table
H = HIGH Logic Level
L = LOW Logic Level
X = Don't Care
Ordering Code Package Number Package Description
DM74ALS520WM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
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
Inputs Output
EN
Data A = B
LA = BL
LA BH
HXH
www.fairchildsemi.com 2
DM74ALS520 DM74ALS521
Logic Diagram
3 www.fairchildsemi.com
DM74ALS520 DM74ALS521
Absolute Maximum Ratings(Note 1)
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.
Recommended Operating Conditions
Electrical Characteristics
over recommended operating free air temperature range. All typical values are measured at V
CC
= 5V, T
A
= 25°C.
Note 2: I
CC
is measured with EN grounded, A and B inputs at 4.5V and outputs OPEN.
Switching Characteristics
over recommended operating free air temperature range
Supply Voltage 7V
Input Voltage 7V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature Range 65°C to +150°C
Typical θ
JA
N Package 62.0°C/W
M Package 82.0°C/W
Symbol Parameter Min Nom Max Units
V
CC
Supply Voltage 4.5 5 5.5 V
V
IH
HIGH Level Input Voltage 2 V
V
IL
LOW Level Input Voltage 0.8 V
I
OH
HIGH Level Output Current 2.6 mA
I
OL
LOW Level Output Current 24 mA
T
A
Free Air Operating Temperature 0 70 °C
Symbol Parameter Conditions Min Typ Max Units
V
IK
Input Clamp Voltage V
CC
= 4.5V, I
I
= 18 mA 1.5 V
V
OH
HIGH Level V
CC
= 4.5V to 5.5V
V
CC
2V
Output Voltage I
OH
= 400 µA
V
CC
= 4.5V
2.4 3.2 V
I
OH
= Max
V
OL
LOW Level Output Voltage V
CC
= 4.5V I
OL
= 24 mA 0.35 0.5 V
I
I
Max HIGH V
CC
= 5.5V V
IH
= 5.5V
Input Current B Input DM74ALS520 0.1 mA
V
IH
= 7V, All Others
I
IH
HIGH Level V
CC
= 5.5V, All Others 20
µA
Input Current V
IH
= 2.7V B Input DM74ALS520 200
I
IL
Low Level Input V
CC
= 5.5V, B Input DM74ALS520 0.6 mA
Current V
IL
= 0.4V All Others 0.1 mA
I
O
Output Drive Current V
CC
= 5.5V V
O
= 2.25V 30 112 mA
I
CC
Supply Current V
CC
= 5.5V (Note 2) 12 19 mA
Symbol Parameter Conditions
From To
Min Max Units
Input Output
t
PLH
Propagation Delay Time V
CC
= 4.5V to 5.5V A or B
A = B 312ns
LOW-to-HIGH Level Output C
L
= 50 pF Data
t
PHL
Propagation Delay Time R
L
= 500 A or B
A = B 520ns
HIGH-to-LOW Level Output Data
t
PLH
Propagation Delay Time
EN A = B 212ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time
EN A = B 522ns
HIGH-to-LOW Level Output
12NEXT