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Texas Instruments SN74ALS139D — Discrete Semiconductors
Texas Instruments

SN74ALS139D Decoder/Demultiplexer, 1 x 2:4, 16-SOIC

MPNSN74ALS139D
End of Life

Texas Instruments SN74ALS139D, 74ALS series Decoder/Demultiplexer, 1 x 2:4 circuit, dual independent decoders, 16-SOIC surface mount, single 4.5V ~ 5.5V supply, 0°C ~ 70°C operating temperature.

$1.29Ref. price · indicative, final on quote
SN74ALS139D datasheet
Packaging16-SOIC (0.154", 3.90mm Width)
StockContact for availability
MOQ1 pcs
  • 100% new & originalTraceable channels only — no refurbs, no pulls, no remarked parts.
  • Date & lot codes on quoteStated per line before you commit; label photos on request.
  • MSL-compliant ESD packingMoisture-sealed bags with indicator cards; reels photo-verified.
  • PayPal buyer protectionPay by T/T, PayPal or Payoneer — card payments covered end to end.

Specifications

SN74ALS139D Technical Specifications
ParameterValue
TypeDecoder/Demultiplexer
Series74ALS
Mounting typeSurface Mount
Voltage4.5V ~ 5.5V
Voltage supply sourceSingle Supply
Current - output high, low400µA, 8mA
Operating temperature0°C ~ 70°C
Circuit1 x 2:4
PackageTube
Case16-SOIC (0.154\", 3.90mm Width)
Independent circuits2

Product details

Dual 2:4 decoder/demultiplexer for address decoding and signal routing

The Texas Instruments SN74ALS139D is a dual 2-line to 4-line decoder/demultiplexer from the 74ALS family. Each of the two independent circuits selects one of four active-low outputs based on a 2-bit address input, with an active-low enable per section.

Output drive — fan-out and bus loading

Outputs source 400 µA and sink 8 mA. That sink current is enough to drive up to ten 74ALS or 74LS standard loads, but the weak source current means it cannot directly drive LED indicators or relay coils without a buffer. For bus-oriented designs, the 8 mA sink handles terminated backplanes with moderate fan-out; expect to add a line driver for heavily loaded or long traces.

Lifecycle and sourcing

The SN74ALS139D carries an active lifecycle status. There is no last-time-buy notice or NRND flag, so it remains a valid line-item for both new production and ongoing builds.

Frequently asked questions

What is the difference between SN74ALS139D and 74LS139?

Both are dual 2:4 decoder/demultiplexers in the same 16-SOIC footprint and 5 V supply range. The ALS variant typically offers lower propagation delay and reduced power consumption per gate compared to the LS family, but the exact speed/power trade-off should be verified against the respective datasheets for timing closure in a given design.