Product details


Technology Family LS Function Encoder/Multiplexer Configuration 2:1 Channels (#) 4 VCC (Min) (V) 4.5 VCC (Max) (V) 5.5 Input type TTL Output type TTL open-in-new Find other Encoders & decoders

Package | Pins | Size

CDIP (J) 16 135 mm² 19.65 x 6.92 CFP (W) 16 69 mm² 10 x 6.7 LCCC (FK) 20 79 mm² 8.89 x 8.89 open-in-new Find other Encoders & decoders


  • Three-State Outputs Interface Directly with System Bus
  • 'LS257B and 'LS258B Offer Three Times the Sink-Current Capability of the Original 'LS257 and 'LS258
  • Same Pin Assignments as SN54LS157, SN74LS157, SN54S157, SN74S157, and SN54LS158, SN74LS158, SN54S158, SN74S158
  • Provides Bus Interface from Multiple Sources in High-Performance Systems

Off state (worst case)


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These devices are designed to multiplex signals from four-bit data sources to four-output data lines in bus-organized systems. The 3-state outputs will not load the data lines when the output control pin (G\) is at a high-logic level.

Series 54LS and 54S are characterized for operation over the full military temperature range of -55°C to 125°C; Series 74LS and 74S are characterized for operation from 0°C to 70°C.


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Technical documentation

= Top documentation for this product selected by TI
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Type Title Date
* Datasheet Quadruple 2-Line To 1-Line Data Selectors/Multiplexers datasheet Mar. 01, 1988
* SMD SN54LS257B SMD 7603701EA Jun. 21, 2016
Selection guide Logic Guide (Rev. AB) Jun. 12, 2017
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) Dec. 02, 2015
User guide LOGIC Pocket Data Book (Rev. B) Jan. 16, 2007
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection Jul. 08, 2004
More literature Logic Cross-Reference (Rev. A) Oct. 07, 2003
Application note TI IBIS File Creation, Validation, and Distribution Processes Aug. 29, 2002
Application note Designing With Logic (Rev. C) Jun. 01, 1997
Application note Designing with the SN54/74LS123 (Rev. A) Mar. 01, 1997
Application note Input and Output Characteristics of Digital Integrated Circuits Oct. 01, 1996
Application note Live Insertion Oct. 01, 1996

Design & development

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CAD/CAE symbols

Package Pins Download
CDIP (J) 16 View options
CFP (W) 16 View options
LCCC (FK) 20 View options

Ordering & quality

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