Product details

Technology family ALS Number of channels 1 Operating temperature range (°C) 0 to 70 Rating Catalog Supply current (max) (µA) 10000
Technology family ALS Number of channels 1 Operating temperature range (°C) 0 to 70 Rating Catalog Supply current (max) (µA) 10000
PDIP (N) 16 181.42 mm² 19.3 x 9.4 SOIC (D) 16 59.4 mm² 9.9 x 6 SOP (NS) 16 79.56 mm² 10.2 x 7.8
  • Designed Specifically for High-Speed Memory Decoders and Data Transmission Systems
  • Incorporate Three Enable Inputs to Simplify Cascading and/or Data Reception
  • Package Options Include Plastic Small-Outline (D) Packages, Ceramic Chip Carriers (FK), and Standard Plastic (N) and Ceramic (J) 300-mil DIPs
  • Designed Specifically for High-Speed Memory Decoders and Data Transmission Systems
  • Incorporate Three Enable Inputs to Simplify Cascading and/or Data Reception
  • Package Options Include Plastic Small-Outline (D) Packages, Ceramic Chip Carriers (FK), and Standard Plastic (N) and Ceramic (J) 300-mil DIPs

The ´ALS138A and ´AS138 are 3-line to 8-line decoders/demultiplexers designed for high-performance memory-decoding or data-routing applications requiring very short propagation delay times. In high-performance systems, these devices can be used to minimize the effects of system decoding. When employed with high-speed memories with a fast enable circuit, the delay times of the decoder and the enable time of the memory are usually less than the typical access time of the memory. The effective system delay introduced by the Schottky-clamped system decoder is negligible.

The conditions at the binary-select (A, B, and C) inputs and the three enable (G1, , and ) inputs select one of eight output lines. Two active-low and one active-high enable inputs reduce the need for external gates or inverters when expanding. A 24-line decoder can be implemented without external inverters and a 32-line decoder requires only one inverter. An enable input can be used as a data input for demultiplexing applications.

The SN54ALS138A and SN54AS138 are characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ALS138A and SN74AS138 are characterized for operation from 0°C to 70°C.

 

 

The ´ALS138A and ´AS138 are 3-line to 8-line decoders/demultiplexers designed for high-performance memory-decoding or data-routing applications requiring very short propagation delay times. In high-performance systems, these devices can be used to minimize the effects of system decoding. When employed with high-speed memories with a fast enable circuit, the delay times of the decoder and the enable time of the memory are usually less than the typical access time of the memory. The effective system delay introduced by the Schottky-clamped system decoder is negligible.

The conditions at the binary-select (A, B, and C) inputs and the three enable (G1, , and ) inputs select one of eight output lines. Two active-low and one active-high enable inputs reduce the need for external gates or inverters when expanding. A 24-line decoder can be implemented without external inverters and a 32-line decoder requires only one inverter. An enable input can be used as a data input for demultiplexing applications.

The SN54ALS138A and SN54AS138 are characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ALS138A and SN74AS138 are characterized for operation from 0°C to 70°C.

 

 

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Technical documentation

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Type Title Date
* Data sheet 3-Line To 8-Line Decoders/Demultiplexers datasheet (Rev. E) 01 Jul 1996
Selection guide Logic Guide (Rev. AB) 12 Jun 2017
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) 02 Dec 2015
User guide LOGIC Pocket Data Book (Rev. B) 16 Jan 2007
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection 08 Jul 2004
Application note TI IBIS File Creation, Validation, and Distribution Processes 29 Aug 2002
Application note Bus-Interface Devices With Output-Damping Resistors Or Reduced-Drive Outputs (Rev. A) 01 Aug 1997
Application note Designing With Logic (Rev. C) 01 Jun 1997
Application note Input and Output Characteristics of Digital Integrated Circuits 01 Oct 1996
Application note Live Insertion 01 Oct 1996
Application note Advanced Schottky (ALS and AS) Logic Families 01 Aug 1995

Design & development

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Evaluation board

14-24-LOGIC-EVM — Logic product generic evaluation module for 14-pin to 24-pin D, DB, DGV, DW, DYY, NS and PW packages

The 14-24-LOGIC-EVM evaluation module (EVM) is designed to support any logic device that is in a 14-pin to 24-pin D, DW, DB, NS, PW, DYY or DGV package,

User guide: PDF | HTML
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Package Pins Download
PDIP (N) 16 View options
SOIC (D) 16 View options
SOP (NS) 16 View options

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