© 2000 Fairchild Semiconductor Corporation DS008442 www.fairchildsemi.comAugust 1986Revised March 2000DM74LS244 Octal 3-STATE Buffer/Line Driver/Line ReceiverDM74LS244Octal 3-STATE Buffer/Line Driver/Line ReceiverGeneral DescriptionThese buffers/line drivers are designed to improve both theperformance and PC board density of 3-STATE buffers/drivers employed as memory-address drivers, clock driv-ers, and bus-oriented transmitters/receivers. Featuring 400mV of hysteresis at each low current PNP data line input,they provide improved noise rejection and high fanout out-puts and can be used to drive terminated lines down to133Ω.Features■ 3-STATE outputs drive bus lines directly■ PNP inputs reduce DC loading on bus lines■ Hysteresis at data inputs improves noise margins■ Typical IOL (sink current) 24 mA■ Typical IOH (source current) −15 mA■ Typical propagation delay timesInverting 10.5 nsNoninverting 12 ns■ Typical enable/disable time 18 ns■ Typical power dissipation (enabled)Inverting 130 mWNoninverting 135 mW Ordering Code:Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.Connection Diagram Function TableL = LOW Logic LevelH = HIGH Logic LevelX = Either LOW or HIGH Logic LevelZ = High ImpedanceOrder Number Package Number Package DescriptionDM74LS244WM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 WideDM74LS244SJ M20D 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm WideDM74LS244N N20A 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 WideInputs OutputGAYLLLLHHHXZwww.fairchildsemi.com 2DM74LS244Absolute 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.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 −15 mAIOLLOW Level Output Current 24 mATAFree Air Operating Temperature 0 70 °CSymbol Parameter Conditions Min Typ MaxUnits(Note 2)VIInput Clamp Voltage VCC = Min, II = −18 mA −1.5 VHYS Hysteresis (VT+ − VT−)VCC = Min 0.2 0.4 VData Inputs OnlyVOHHIGH Level Output Voltage VCC = Min, VIH = Min2.7VIL = Max, IOH = −1 mAVCC = Min, VIH = Min2.4 3.4 VVIL = Max, IOH = −3 mAVCC = Min, VIH = Min2VIL = 0.5V, IOH = MaxVOLLOW Level Output Voltage VCC = Min IOL = 12 mA 0.4VVIL = Max IOL = Max 0.5VIH = MinIOZHOff-State Output Current, VCC = Max VO = 2.7V 20 µAHIGH Level Voltage Applied VIL = MaxIOZLOff-State Output Current, VIH = Min VO = 0.4V −20 µALOW Level Voltage AppliedIIInput Current at Maximum VCC = Max VI = 7V 0.1 mAInput VoltageIIHHIGH Level Input Current VCC = Max VI = 2.7V 20 µAIILLOW Level Input Current VCC = Max VI = 0.4V −0.5 −200 µAIOSShort Circuit Output Current VCC = Max (Note 3) −40 −225 mAICCSupply Current VCC = Max, Outputs HIGH 13 23Outputs Open Outputs LOW 27 46 mAOutputs Disabled 32 543 www.fairchildsemi.comDM74LS244Switching Characteristics at VCC = 5V, TA = 25°C Symbol Parameter Conditions Max UnitstPLHPropagation Delay Time CL = 45 pF18 nsLOW-to-HIGH Level Output RL = 667ΩtPHLPropagation Delay Time CL = 45 pF18 nsHIGH-to-LOW Level Output RL = 667ΩtPZLOutput Enable Time to CL = 45 pF30 nsLOW Level RL = 667ΩtPZHOutput Enable Time to CL = 45 pF23 nsHIGH Level RL = 667ΩtPLZOutput Disable Time CL = 5 pF25 nsfrom LOW Level RL = 667ΩtPHZOutput Disable Time CL = 5 pF18 nsfrom HIGH Level RL = 667ΩtPLHPropagation Delay Time CL = 150 pF21 nsLOW-to-HIGH Level Output RL = 667ΩtPHLPropagation Delay Time CL = 150 pF22 nsHIGH-to-LOW Level Output RL = 667ΩtPZLOutput Enable Time to CL = 150 pF33 nsLOW Level RL = 667ΩtPZHOutput Enable Time to CL = 150 pF26 nsHIGH Level RL = 667Ωwww.fairchildsemi.com 4DM74LS244Physical Dimensions inches (millimeters) unless otherwise noted20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 WidePackage Number M20B5 www.fairchildsemi.comDM74LS244Physical Dimensions inches (millimeters) unless otherwise noted (Continued)20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm WidePackage Number M20Dwww.fairchildsemi.com 6DM74LS244 Octal 3-STATE Buffer/Line Driver/Line ReceiverPhysical Dimensions inches (millimeters) unless otherwise noted (Continued)20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 WidePackage Number N20AFairchild 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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