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54LS283 DM54LS283 DM74LS283 4-Bit Binary Adders with Fast Carry

June 1989

54LS283 DM54LS283 DM74LS283 4-Bit Binary Adders with Fast Carry
General Description
These full adders perform the addition of two 4-bit binary numbers The sum (R) outputs are provided for each bit and the resultant carry (C4) is obtained from the fourth bit These adders feature full internal look ahead across allfour bits This provides the system designer with partial lookahead performance at the economy and reduced package count of a ripple-carry implementation The adder logic including the carry is implemented in its true form meaning that the end-around carry can be accomplished without the need for logic or level inversion

Features
Y Y

Y

Y Y

Full-carry look-ahead across the four bitsSystems achieve partial look-ahead performance with the economy of ripple carry Typical add times Two 8-bit words 25 ns Two 16-bit words 45 ns Typical power dissipation per 4-bit adder 95 mW Alternate Military Aerospace device (54LS283) is available Contact a National Semiconductor Sales Office Distributor for specifications

Connection Diagram
Dual-In-Line Package

TL F 6421 – 1

Order Number54LS283DMQB 54LS283FMQB 54LS283LMQB DM54LS283J DM54LS283W DM74LS283M or DM74LS283N See NS Package Number E20A J16A M16A N16E or W16A

C1995 National Semiconductor Corporation

TL F 6421

RRD-B30M105 Printed in U S A

Absolute Maximum Ratings (Note)
If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability andspecifications Supply Voltage 7V Input Voltage 7V Operating Free Air Temperature Range b 55 C to a 125 C DM54LS and 54LS DM74LS 0 C to a 70 C Storage Temperature Range
b 65 C to a 150 C

Note 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’’ table are not guaranteed at the absolute maximum ratings The ‘‘Recommended Operating Conditions’’ table will define the conditions for actual device operation

Recommended Operating Conditions
Symbol VCC VIH VIL IOH IOL TA Parameter Min Supply Voltage High Level Input Voltage Low Level Input Voltage High Level Output Current Low Level Output Current Free Air OperatingTemperature
b 55

DM54LS283 Nom 5 Max 55 Min 4 75 2 07
b0 4

DM74LS283 Nom 5 Max 5 25

Units V V 08
b0 4

45 2

V mA mA C

4 125 0

8 70

Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted)
Symbol VI VOH Parameter Input Clamp Voltage High Level Output Voltage Low Level Output Voltage Conditions VCC e Min II e b18 mA VCC e Min IOH eMax VIL e Max VIH e Min VCC e Min IOL e Max VIL e Max VIH e Min IOL e 4 mA VCC e Min II Input Current Input Voltage Max VCC e Max VI e 7V VCC e Max VI e 2 7V VCC e Max VI e 0 4V VCC e Max (Note 2) VCC e Max (Note 3) VCC e Max (Note 4) DM54 DM74 DM54 DM74 DM74 A B C0 A B C0 A B C0 DM54 DM74
b 20 b 20

Min

Typ (Note 1)

Max
b1 5

Units V V

25 27

34 34 0 25 0 35 0 25 04 05 04 02 01 4020
b0 8 b0 4 b 100 b 100

VOL

V

mA

IIH

High Level Input Current Low Level Input Current Short Circuit Output Current Supply Current Supply Current

mA

IIL

mA

IOS

mA mA mA

ICC1 ICC2

19 22

34 39

Note 1 All typicals are at VCC e 5V TA e 25 C Note 2 Not more than one output should be shorted at a time and the duration should not exceed one second Note 3 ICC1is measured with all outputs open all B inputs low and all other inputs at 4 5V or all inputs at 4 5V Note 4 ICC2 is measured with all outputs open and all inputs grounded

2

Switching Characteristics at VCC e 5V and TA e 25 C (See Section 1 for Test Waveforms and Output Load)
Symbol Parameter From (Input) To (Output) C0 to R1 R2 C0 to R1 R2 C0 to R3 C0 to R3 C0 to R4 C0 to R4 Ai or Bi...
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