© 2000 Fairchild Semiconductor Corporation DS006421 www.fairchildsemi.comAugust 1986Revised March 2000DM74LS283 4-Bit Binary Adder with Fast CarryDM74LS2834-Bit Binary Adder with Fast CarryGeneral DescriptionThese full adders perform the addition of two 4-bit binarynumbers. The sum (∑) outputs are provided for each bitand the resultant carry (C4) is obtained from the fourth bit.These adders feature full internal look ahead across all fourbits. This provides the system designer with partial look-ahead performance at the economy and reduced packagecount of a ripple-carry implementation.The adder logic, including the carry, is implemented in itstrue form meaning that the end-around carry can beaccomplished without the need for logic or level inversion.Features■ Full-carry look-ahead across the four bits■ Systems achieve partial look-ahead performance withthe economy of ripple carry■ Typical add timesTwo 8-bit words 25 nsTwo 16-bit words 45 ns■ Typical power dissipation per 4-bit adder 95 mW Ordering Code:Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.Connection DiagramOrder Number Package Number Package DescriptionDM74LS283M M16A 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 NarrowDM74LS283N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Widewww.fairchildsemi.com 2DM74LS283Function TableH = HIGH Level, L = LOW LevelInput conditions at A1, B1, A2, B2, and C0 are used to determine outputs ∑1 and ∑2 and the value of the internal carry C2. The values at C2, A3, B3, A4, and B4 are then used to determine outputs ∑3, ∑4, and C4.Logic Diagram3 www.fairchildsemi.comDM74LS283Absolute Maximum Ratings(Note 1)Note 1: The “Absolute Maximum Ratings” are those values beyond whichthe safety of the device cannot be guaranteed. The device should not beoperated at these limits. The parametric values defined in the ElectricalCharacteristics tables are not guaranteed at the absolute maximum ratings.The “Recommended Operating Conditions” table will define the conditionsfor actual device operation.Recommended Operating ConditionsElectrical Characteristics over recommended operating free air temperature range (unless otherwise noted)Note 2: All typicals are at VCC = 5V, TA = 25°C.Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.Note 4: ICC1 is measured with all outputs OPEN, all B inputs LOW and all other inputs at 4.5V, or all inputs at 4.5V.Note 5: ICC2 is measured with all outputs OPEN and all inputs GROUNDED.Supply Voltage 7VInput Voltage 7VOperating Free Air Temperature Range 0°C to +70°CStorage Temperature Range −65°C to +150°CSymbol Parameter Min Nom Max UnitsVCCSupply Voltage 4.75 5 5.25 VVIHHIGH Level Input Voltage 2 VVILLOW Level Input Voltage 0.8 VIOHHIGH Level Output Current −0.4 mAIOLLOW Level Output Current 8 mATAFree Air Operating Temperature 0 70 °CSymbol Parameter Conditions MinTypMax Units(Note 2)VIInput Clamp Voltage VCC = Min, II = −18 mA −1.5 VVOHHIGH Level VCC = Min, IOH = Max2.7 3.4 VOutput Voltage VIL = Max, VIH = MinVOLLOW Level VCC = Min, IOL = Max0.35 0.5Output Voltage VIL = Max, VIH = Min VIOL = 4 mA, VCC = Min 0.25 0.4IIInput Current @ Max VCC = Max A, B 0.2mAInput Voltage VI = 7V C0 0.1IIHHIGH Level VCC = Max A, B 40µAInput Current VI = 2.7V C0 20IILLOW Level VCC = Max A, B −0.8mAInput Current VI = 0.4V C0 −0.4IOSShort Circuit Output Current VCC = Max −20 −100 mAICC1Supply Current VCC = Max (Note 4) 19 34 mAICC2Supply Current VCC = Max (Note 5) 22 39 mAwww.fairchildsemi.com 4DM74LS283Switching Characteristics at VCC = 5V and TA = 25°C From (Input) RL = 2 kΩSymbol ParameterTo (Output)CL = 15 pF CL = 50 pF UnitsMinMaxMinMaxtPLHPropagation Delay TimeC0 to ∑1, ∑22428nsLOW-to-HIGH Level OutputtPHLPropagation Delay TimeC0 to ∑1, ∑22430nsHIGH-to-LOW Level OutputtPLHPropagation Delay TimeC0 to ∑32428nsLOW-to-HIGH Level OutputtPHLPropagation Delay TimeC0 to ∑32430nsHIGH-to-LOW Level OutputtPLHPropagation Delay TimeC0 to ∑42428nsLOW-to-HIGH Level OutputtPHLPropagation Delay TimeC0 to ∑42430nsHIGH-to-LOW Level OutputtPLHPropagation Delay TimeAi or Bi to ∑i24 28 nsLOW-to-HIGH Level OutputtPHLPropagation Delay TimeAi or Bi to ∑i24 30 nsHIGH-to-LOW Level OutputtPLHPropagation Delay TimeC0 to C4 17 24 nsLOW-to-HIGH Level OutputtPHLPropagation Delay TimeC0 to C4 17 25 nsHIGH-to-LOW Level OutputtPLHPropagation Delay TimeAi or Bi to C4 17 24 nsLOW-to-HIGH Level OutputtPHLPropagation Delay TimeAi or Bi to C4 17 26 nsHIGH-to-LOW Level Output5 www.fairchildsemi.comDM74LS283Physical Dimensions inches (millimeters) unless otherwise noted16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 NarrowPackage Number M16Awww.fairchildsemi.com 6DM74LS283 4-Bit Binary Adder with Fast CarryPhysical Dimensions inches (millimeters) unless otherwise noted (Continued)16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 WidePackage Number N16EFairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied andFairchild reserves the right at any time without notice to change said circuitry and specifications.LIFE SUPPORT POLICYFAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORTDEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILDSEMICONDUCTOR CORPORATION. As used herein:1. Life support devices or systems are devices or systemswhich, (a) are intended for surgical implant into thebody, or (b) support or sustain life, and (c) whose failureto perform when properly used in accordance withinstructions for use provided in the labeling, can be rea-sonably expected to result in a significant injury to theuser.2. A critical component in any component of a life supportdevice or system whose failure to perform can be rea-sonably expected to cause the failure of the life supportdevice or system, or to affect its safety or
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