SCAS294O JANUARY   1993  – June 2015 SN54LVC257A , SN74LVC257A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Options
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information: 16-Pin Packages
    5. 7.5  Thermal Information: 20-Pin Package
    6. 7.6  Electrical Characteristics
    7. 7.7  SN54LVC257A Switching Characteristics
    8. 7.8  SN74LVC257A Switching Characteristics
    9. 7.9  Operating Characteristics
    10. 7.10 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
    4. 9.4 Device Functional Modes
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Related Links
    3. 13.3 Community Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7 Specifications

7.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
VCC Supply voltage –0.5 6.5 V
VI Input voltage(2) –0.5 6.5 V
VO Output voltage(2)(3) –0.5 VCC + 0.5 V
IIK Input clamp current VI < 0 –50 mA
IOK Output clamp current VO < 0 –50 mA
IO Continuous output current ±50 mA
Continuous current through VCC or GND ±100 mA
Tstg Storage temperature –65 150 °C
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) The input negative-voltage and output voltage ratings may be exceeded if the input and output current ratings are observed.
(3) The value of VCC is provided in the recommended operating conditions table.

7.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins(1) ±2000 V
Charged-device model (CDM), per JEDEC specification JESD22-C101, all pins(2) ±1000
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

7.3 Recommended Operating Conditions

See (1)
SN54LVC257A SN74LVC257A UNIT
MIN MAX MIN MAX
VCC Supply voltage Operating 2 3.6 1.65 3.6 V
Data retention only 1.5 1.5
VIH High-level input voltage VCC = 1.65 V to 1.95 V 0.65 × VCC V
VCC = 2.3 V to 2.7 V 1.7
VCC = 2.7 V to 3.6 V 2 2
VIL Low-level input voltage VCC = 1.65 V to 1.95 V 0.35 × VCC V
VCC = 2.3 V to 2.7 V 0.7
VCC = 2.7 V to 3.6 V 0.8 0.8
VI Input voltage 0 5.5 0 5.5 V
VO Output voltage 0 VCC 0 VCC V
IOH High-level output current VCC = 1.65 V –4 mA
VCC = 2.3 V –8
VCC = 2.7 V –12 –12
VCC = 3 V –24 –24
IOL Low-level output current VCC = 1.65 V 4 mA
VCC = 2.3 V 8
VCC = 2.7 V 12 12
VCC = 3 V 24 24
Δt/Δv Input transition rise or fall rate 10 10 ns/V
TA Operating free-air temperature –55 125 –40 85 °C
(1) 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, SCBA004.

7.4 Thermal Information: 16-Pin Packages

THERMAL METRIC(1) SN54LVC257A, SN74LVC257A UNIT
D (SOIC)(2) DB (SSOP)(2) NS (SO)(2) PW (TSSOP)(2)
16 PINS
RθJA Junction-to-ambient thermal resistance 73 82 64 108 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.
(2) The package thermal impedance is calculated in accordance with JESD 51-7.

7.5 Thermal Information: 20-Pin Package

THERMAL METRIC(1) SN54LVC257A UNIT
RGY (LCCC)(2)
20 PINS
RθJA Junction-to-ambient thermal resistance 39 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.
(2) The package thermal impedance is calculated in accordance with JESD 51-5.

7.6 Electrical Characteristics

over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER TEST CONDITIONS VCC SN54LVC257A SN74LVC257A UNIT
MIN TYP(1) MAX MIN TYP(1) MAX
VOH IOH = –100 μA 1.65 V to 3.6 V VCC – 0.2 V
IOH = –100 μA 2.7 V to 3.6 V VCC – 0.2
IOH = –4 mA 1.65 V 1.2
IOH = –8 mA 2.3 V 1.7
IOH = –12 mA 2.7 V 2.2 2.2
3 V 2.4 2.4
IOH = –24 mA 3 V 2.2 2.2
VOL IOL = 100 μA 1.65 V to 3.6 V 0.2 V
2.7 V to 3.6 V 0.2
IOL = 4 mA 1.65 V 0.45
IOL = 8 mA 2.3 V 0.7
IOL = 12 mA 2.7 V 0.4 0.4
IOL = 24 mA 3 V 0.55 0.55
II VI = 5.5 V or GND 3.6 V ±5 ±5 μA
IOZ VO = VCC or GND 3.6 V ±15 ±10 μA
ICC VI = VCC or GND, IO = 0 3.6 V 10 10 μA
ΔICC One input at VCC – 0.6 V,
Other inputs at VCC or GND		 2.7 V to 3.6 V 500 500 μA
Ci VI = VCC or GND 3.3 V 5 5 pF
Co VO = VCC or GND 3.3 V 5 5 pF
(1) All typical values are at VCC = 3.3 V, TA = 25°C.

7.7 SN54LVC257A Switching Characteristics

over recommended operating free-air temperature range (unless otherwise noted) (see Figure 3)
PARAMETER FROM
(INPUT)		 TO
(OUTPUT)		 SN54LVC257A UNIT
VCC = 2.7 V VCC = 3.3 V
± 0.3 V
MIN MAX MIN MAX
tpd A or B Y 5.4 1 4.6 ns
A/B 7.5 1 6.4
ten OE Y 6.7 1 5.6 ns
tdis OE Y 4.7 0.5 4.3 ns
tsk(o) 1 ns

7.8 SN74LVC257A Switching Characteristics

over recommended operating free-air temperature range (unless otherwise noted) (see Figure 3)
PARAMETER FROM
(INPUT)		 TO
(OUTPUT)		 SN74LVC257A UNIT
VCC = 1.8 V
± 0.15 V		 VCC = 2.5 V
± 0.2 V		 VCC = 2.7 V VCC = 3.3 V
± 0.3 V
MIN MAX MIN MAX MIN MAX MIN MAX
tpd A or B Y 1 13.5 1 7.4 1 5.4 1 4.6 ns
A/B 1 15.6 1 9.5 1 7.5 1 6.4
ten OE Y 1 14.6 1 8.7 1 6.7 1 5.6 ns
tdis OE Y 1 15.4 1 6.7 1 4.7 1 4.3 ns
tsk(o) 1 ns

7.9 Operating Characteristics

TA = 25°C
PARAMETER TEST CONDITIONS VCC = 1.8 V VCC = 2.5 V VCC = 3.3 V UNIT
TYP TYP TYP
Cpd Power dissipation capacitance f = 10 MHz 13.5 14.5 15.5 pF

7.10 Typical Characteristics

SN54LVC257A SN74LVC257A graph_5a_scas414.gifFigure 1. Propagation Delay (Low to High Transition)
vs Load Capacitance
SN54LVC257A SN74LVC257A graph_5b_scas414.gifFigure 2. Propagation Delay (High to Low Transition)
vs Load Capacitance