SN74HC257DG4


        


 
  
SCLS072D − NOVEMBER 1988 − REVISED SEPTEMBER 2003 D Operating Voltage Range of 4.5 V to 5.5 V D High-Current 3-State Outputs Interface Directly With System Bus D Typical tpd = 17 ns D Low Power Consumption, 80-µA Max ICC D ±6-mA Output Drive at 5 V 16 2 15 3 14 4 13 5 12 6 11 7 10 8 9 1A A/B NC VCC OE VCC OE 4A 4B 4Y 3A 3B 3Y 1B 1Y NC 2A 2B 4 3 2 1 20 19 18 5 17 6 16 7 15 8 14 9 10 11 12 13 4A 4B NC 4Y 3A 2Y GND NC 3Y 3B 1 D Sources in High-Performance Systems Buffered Inputs and Outputs SN54HCT257 . . . FK PACKAGE (TOP VIEW) SN54HCT257 . . . J PACKAGE SN74HCT257 . . . D OR N PACKAGE (TOP VIEW) A/B 1A 1B 1Y 2A 2B 2Y GND D Low Input Current of 1 µA Max D Inputs Are TTL-Voltage Compatible D Provide Bus Interface From Multiple NC − No internal connection description/ordering information The ’HCT257 devices are designed to multiplex signals from 4-bit data sources to 4-output data lines in bus-organized systems. The 3-state outputs do not load the data lines when the output-enable (OE) input is at the high logic level. To ensure the high-impedance state during power up or power down, OE should be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver. ORDERING INFORMATION PACKAGE† TA PDIP − N −40°C to 85°C SOIC − D CDIP − J ORDERABLE PART NUMBER Tube of 25 SN74HCT257N Tube of 40 SN74HCT257D Reel of 2500 SN74HCT257DR Reel of 250 SN74HCT257DT Tube of 25 SNJ54HCT257J TOP-SIDE MARKING SN74HCT257N HCT257 SNJ54HCT257J −55°C to 125°C LCCC − FK Tube of 55 SNJ54HCT257FK SNJ54HCT257FK † Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at www.ti.com/sc/package. Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. Copyright  2003, Texas Instruments Incorporated 


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SCLS072D − NOVEMBER 1988 − REVISED SEPTEMBER 2003 FUNCTION TABLE INPUTS OUTPUT Y DATA OE SELECT A/B A B H X X X Z L L L X L L L H X H L H X L L L H X H H logic diagram (positive logic) OE A/B 1A 1B 2A 2B 3A 3B 4A 4B 15 1 2 4 3 5 7 2Y 6 11 9 3Y 10 14 12 13 Pin numbers shown are for the D, J, and N packages. 2 1Y POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 4Y 

        


 
  
SCLS072D − NOVEMBER 1988 − REVISED SEPTEMBER 2003 absolute maximum ratings over operating free-air temperature range (unless otherwise noted)† Supply voltage range, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V Input clamp current, IIK (VI < 0 or VI > VCC) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA Output clamp current, IOK (VO < 0 or VO > VCC) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA Continuous output current, IO (VO = 0 to VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±35 mA Continuous current through VCC or GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±70 mA Package thermal impedance, θJA (see Note 2): D package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73°C/W N package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67°C/W Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C † Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed. 2. The package thermal impedance is calculated in accordance with JESD 51-7. recommended operating conditions (see Note 3) SN54HCT257 MIN NOM MAX MIN NOM MAX 4.5 5 5.5 4.5 5 5.5 VCC VIH Supply voltage VIL VI Low-level input voltage Input voltage 0 VO tt Output voltage 0 High-level input voltage VCC = 4.5 V to 5.5 V VCC = 4.5 V to 5.5 V SN74HCT257 2 2 Input transition (rise and fall) time V V 0.8 VCC VCC UNIT 0 0 500 0.8 V VCC VCC V 500 ns V TA Operating free-air temperature −55 125 −40 85 °C NOTE 3: All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report, Implications of Slow or Floating CMOS Inputs, literature number SCBA004. electrical characteristics over recommended operating free-air temperature range (unless otherwise noted) PARAMETER TEST CONDITIONS VCC VOH VI = VIH or VIL IOH = −20 µA IOH = −6 mA 4.5 V VOL VI = VIH or VIL IOL = 20 µA IOL = 6 mA 4.5 V II IOZ VI = VCC or 0 VO = VCC or 0, ICC ∆ICC‡ VI = VIH or VIL VI = VCC or 0, IO = 0 One input at 0.5 V or 2.4 V, Other inputs at 0 or VCC Ci TA = 25°C MIN TYP MAX SN54HCT257 MIN MAX SN74HCT257 MIN 4.4 4.499 4.4 4.4 3.98 4.3 3.7 3.84 MAX UNIT V 0.001 0.1 0.1 0.1 0.17 0.26 0.4 0.33 5.5 V ±0.1 ±100 ±1000 ±1000 nA 5.5 V ±0.01 ±0.5 ±10 ±5 µA 8 160 80 µA 1.4 2.4 3 2.9 mA 3 10 10* 10 pF 5.5 V 5.5 V 4.5 V to 5.5 V V * On products compliant to MIL-PRF-38535, this parameter is not production tested. ‡ This is the increase in supply current for each input that is at one of the specified TTL voltage levels, rather than 0 V or VCC.  3 ')"*%("' #"'#&*' +*"!$# ' & )"*%(4& "* !&2' +(& ") !&4&-"+%&'. (*(#&*# !(( ('! "&* +&#)#("' (*& !&2' 2"(-. &/( '*$%&' *&&*4& & *2 " #('2& "* !#"''$& && +*"!$# 0"$ '"#&. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 3 

        


 
  
SCLS072D − NOVEMBER 1988 − REVISED SEPTEMBER 2003 switching characteristics over recommended operating free-air temperature range, CL = 50 pF (unless otherwise noted) (see Figure 1) PARAMETER FROM (INPUT) TO (OUTPUT) A or B Y tpd Y A/B ten OE Y tdis OE Y tt Any VCC MIN TA = 25°C TYP MAX SN54HCT257 MIN MAX SN74HCT257 MIN MAX 4.5 V 20 30 45 38 5.5 V 17 27 40 34 4.5 V 20 30 45 38 5.5 V 17 27 40 34 4.5 V 20 30 45 38 5.5 V 17 27 40 34 4.5 V 20 30 45 38 5.5 V 17 27 40 34 4.5 V 8 15 22 19 5.5 V 7 14 21 17 UNIT ns ns ns ns switching characteristics over recommended operating free-air temperature range, CL = 150 pF (unless otherwise noted) (see Figure 1) PARAMETER FROM (INPUT) TO (OUTPUT) A or B Y tpd ten A/B Y OE Y tt Any VCC MIN TA = 25°C TYP MAX SN54HCT257 MIN MAX SN74HCT257 MIN MAX 4.5 V 22 38 57 48 5.5 V 19 35 53 44 4.5 V 22 38 57 48 5.5 V 19 35 53 44 4.5 V 23 40 60 50 5.5 V 20 38 57 48 4.5 V 17 42 63 53 5.5 V 14 38 57 48 UNIT ns ns ns operating characteristics, TA = 25°C PARAMETER Cpd TEST CONDITIONS Power dissipation capacitance No load  3 ')"*%("' #"'#&*' +*"!$# ' & )"*%(4& "* !&2' +(& ") !&4&-"+%&'. (*(#&*# !(( ('! "&* +&#)#("' (*& !&2' 2"(-. &/( '*$%&' *&&*4& & *2 " #('2& "* !#"''$& && +*"!$# 0"$ '"#&. 4 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 TYP 13 UNIT pF 

        


 
  
SCLS072D − NOVEMBER 1988 − REVISED SEPTEMBER 2003 PARAMETER MEASUREMENT INFORMATION VCC From Output Under Test CL (see Note A) PARAMETER S1 Test Point tPZH ten RL S2 1 kΩ tPZL tPHZ tdis 3V 1.3 V 0V tPLH In-Phase Output 1.3 V 10% tPHL 90% 90% tr tPHL Out-ofPhase Output 90% VOH 1.3 V 10% V OL tf tPLH 1.3 V 10% 1.3 V 10% tf S2 50 pF or 150 pF Open Closed Closed Open Open Closed Closed Open Open Open 50 pF tPLZ −− LOAD CIRCUIT 1.3 V S1 1 kΩ tpd or tt Input CL RL Output Control (Low-Level Enabling) 50 pF or 150 pF 3V 1.3 V 1.3 V 0V tPZL Output Waveform 1 (See Note B) tPLZ ≈VCC 1.3 V 10% tPZH 90% VOH VOL tr VOLTAGE WAVEFORMS OUTPUT AND 3-STATE BIDIRECTIONAL I/O PROPAGATION DELAY TIME Output Waveform 2 (See Note B) VOL tPHZ 1.3 V 90% VOH ≈0 V VOLTAGE WAVEFORMS ENABLE AND DISABLE TIMES FOR 3-STATE OUTPUTS NOTES: A. CL includes probe and test-fixture capacitance. B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control. Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control. C. Phase relationships between waveforms were chosen arbitrarily. All input pulses are supplied by generators having the following characteristics: PRR ≤ 1 MHz, ZO = 50 Ω, tr = 6 ns, tf = 6 ns. D. The outputs are measured one at a time with one input transition per measurement. E. tPLZ and tPHZ are the same as tdis. F. tPZL and tPZH are the same as ten. G. tPLH and tPHL are the same as tpd. Figure 1. Load Circuit and Voltage Waveforms POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 5 PACKAGE OPTION ADDENDUM www.ti.com 14-Oct-2022 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) Device Marking (3) Samples (4/5) (6) SN74HCT257D ACTIVE SOIC D 16 40 RoHS & Green NIPDAU Level-1-260C-UNLIM -40 to 85 HCT257 Samples SN74HCT257DR ACTIVE SOIC D 16 2500 RoHS & Green NIPDAU Level-1-260C-UNLIM -40 to 85 HCT257 Samples SN74HCT257N ACTIVE PDIP N 16 25 RoHS & Green NIPDAU N / A for Pkg Type -40 to 85 SN74HCT257N Samples (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of