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74HC138

3-Line To 8-Line Decoders/Demultiplexers

The 74HC138 is a 3-line to 8-line decoders/demultiplexers from Texas Instruments. View the full 74HC138 datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

Official 74HC138 datasheet (PDF) — the source this page was extracted from.

Manufacturer

Texas Instruments

Category

3-Line To 8-Line Decoders/Demultiplexers

Package

SOIC (16), SSOP (16)

74HC138 Key Specifications

ParameterValue
High-level output voltage (VOH)3.98 V (min) at IOH = -4 mA, VCC = 4.5 V (SN74HC138)
Low-level output voltage (VOL)0.26 V (max) at IOL = 4 mA, VCC = 4.5 V (SN74HC138)
Input current (II)±100 nA (max) at VCC = 6 V (SN74HC138)
Quiescent supply current (ICC)80 μA (max) at VCC = 6 V (SN74HC138)
Propagation delay (tpd) from A, B, or C to any Y15 ns (typ) at VCC = 6 V, CL = 50 pF
Output transition time (tt)6 ns (typ) at VCC = 6 V, CL = 50 pF
Input capacitance (Ci)10 pF (max) at VCC = 2 V to 6 V
Output drive±4-mA at 5 V

74HC138 Overview

Part: SN54HC138, SN74HC138 from Texas Instruments

Type: 3-Line To 8-Line Decoders/Demultiplexers

Description: The SNx4HC138 devices are 3-Line To 8-Line Decoders/Demultiplexers designed for high-performance memory-decoding or data-routing applications, featuring a wide operating voltage range of 2 V to 6 V, low power consumption (80-μA max ICC for SN74HC138), and a typical propagation delay of 15 ns.

Operating Conditions:

  • Supply voltage: 2 V to 6 V
  • Operating temperature:
    • SN54HC138: -55 to 125 °C
    • SN74HC138: -40 to 85 °C
  • Input voltage: 0 to VCC V
  • Output voltage: 0 to VCC V

Absolute Maximum Ratings:

  • Max supply voltage: 7 V
  • Max continuous current: ±25 mA (output)
  • Max junction/storage temperature: 150 °C

Key Specs:

  • High-level output voltage (VOH): 3.98 V (min) at IOH = -4 mA, VCC = 4.5 V (SN74HC138)
  • Low-level output voltage (VOL): 0.26 V (max) at IOL = 4 mA, VCC = 4.5 V (SN74HC138)
  • Input current (II): ±100 nA (max) at VCC = 6 V (SN74HC138)
  • Quiescent supply current (ICC): 80 μA (max) at VCC = 6 V (SN74HC138)
  • Propagation delay (tpd) from A, B, or C to any Y: 15 ns (typ) at VCC = 6 V, CL = 50 pF
  • Output transition time (tt): 6 ns (typ) at VCC = 6 V, CL = 50 pF
  • Input capacitance (Ci): 10 pF (max) at VCC = 2 V to 6 V
  • Output drive: ±4-mA at 5 V

Features:

  • Targeted Specifically for High-Speed Memory Decoders and Data-Transmission Systems
  • Wide Operating Voltage Range (2 V to 6 V)
  • Outputs Can Drive Up To 10 LSTTL Loads
  • Low Power Consumption, 80-μA Maximum ICC
  • Typical t pd = 15 ns
  • ±4-mA Output Drive at 5 V
  • Low Input Current of 1-μA Maximum
  • Active Low Outputs (Selected Output is Low)
  • Incorporate Three Enable Inputs to Simplify Cascading or Data Reception

Applications:

  • LED Displays
  • Servers
  • White Goods
  • Power Infrastructure
  • Building Automation
  • Factory Automation

Package:

  • SOIC (16)
  • SSOP (16)
  • PDIP (16)
  • SO (16)
  • TSSOP (16)
  • CDIP (16)
  • CFP (16)
  • LCCC (20)

74HC138 Features

  • Targeted Specifically for High-Speed Memory Decoders and Data-Transmission Systems
  • Wide Operating Voltage Range (2 V to 6 V)
  • Outputs Can Drive Up To 10 LSTTL Loads
  • Low Power Consumption, 80-μA Maximum ICC
  • Typical t pd = 15 ns
  • ±4-mA Output Drive at 5 V
  • Low Input Current of 1-μA Maximum
  • Active Low Outputs ( Selected Output is Low)
  • Incorporate Three Enable Inputs to Simplify Cascading or Data Reception

74HC138 Applications

  • LED Displays
  • Servers
  • White Goods
  • Power Infrastructure
  • Building Automation
  • Factory Automation

74HC138 Pin Configuration

74HC138 Electrical Characteristics

over operating free-air temperature range (unless otherwise noted)

PARAMETERTEST CONDITIONSTEST CONDITIONSTEST CONDITIONSMINTYPMAXUNIT
V OHV I = V IH or V ILI OH = -20 μAV CC = 2 V1.9V
V OHV I = V IH or V ILI OH = -20 μAV CC = 4.5 V4.4V
V OHV I = V IH or V ILI OH = -20 μAV CC = 6 V5.9V
V OHV I = V IH or V ILI OH = -4 mA, V CC = 4.5 VI OH = -4 mA, V CC = 4.5 V3.84V
V OHV I = V IH or V ILI OH = -5.2 mA, V CC = 6 VI OH = -5.2 mA, V CC = 6 V5.34V
V OLV I = V IH or V ILI OL = 20 μAV CC = 2 V0.1V
V OLV I = V IH or V ILI OL = 20 μAV CC = 4.5 V0.1V
V OLV I = V IH or V ILI OL = 20 μAV CC = 6 V0.1V
V OLV I = V IH or V ILI OL = 4 mA, V CC = 4.5 VI OL = 4 mA, V CC = 4.5 V0.33V
V OLV I = V IH or V ILI OL = 5.2 mA, V CC = 6 VI OL = 5.2 mA, V CC = 6 V0.33V
I IV I = V CC or 0, V CC = 6 VV I = V CC or 0, V CC = 6 VV I = V CC or 0, V CC = 6 V±1000nA
I CCV I = V CC or 0, I O = 0, V CC = 6 VV I = V CC or 0, I O = 0, V CC = 6 VV I = V CC or 0, I O = 0, V CC = 6 V80μA
C iV CC = 2 V to 6 VV CC = 2 V to 6 VV CC = 2 V to 6 V10pF

74HC138 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted) (1)

MINMAXUNIT
V CCSupply voltage rangeSupply voltage range-0.57V
I IKInput clamp current (2)V I < 0 or V I > V CC±20mA
I OKOutput clamp current (2)V O < 0 or V O > V CC±20mA
I OContinuous output currentV O = 0 to V CC±25mA
Continuous current through V CC or GNDContinuous current through V CC or GND±50mA
T JJunction temperatureJunction temperature150°C
T stgStorage temperatureStorage temperature-65150°C

74HC138 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted) (1)

MINNOMMAXUNIT
V CCSupply voltage256V
V IHHigh-level input voltageV CC = 2 V1.5V
V IHHigh-level input voltageV CC = 4.5 V3.15V
V IHHigh-level input voltageV CC = 6 V4.2V
V ILLow-level input voltageV CC = 2 V0.5V
V ILLow-level input voltageV CC = 4.5 V1.35V
V ILLow-level input voltageV CC = 6 V1.8V
V IInput voltage0V CCV
V OOutput voltage0V CCV
Δt/ΔvInput transition rise or fall timeV CC = 2 V1000ns
Δt/ΔvInput transition rise or fall timeV CC = 4.5 V500ns
Δt/ΔvInput transition rise or fall timeV CC = 6 V400ns
C pdPower dissipation capacitance (no load)85pF
T AOperating free-air temperatureSN54HC138-55125°C
T AOperating free-air temperatureSN74HC138-4085°C

74HC138 Thermal Information

SN74HC138SN74HC138SN74HC138SN74HC138SN74HC138
THERMAL METRIC (1)THERMAL METRIC (1)D (SOIC)DB (SSOP)N (PDIP)NS (SO)PW (TSSOP)
16 PINS16 PINS16 PINS16 PINS16 PINS
R θJAJunction-to-ambient thermal resistance87.3104.354.891.1141.6
R θJC(top)Junction-to-case (top) thermal resistance45.854.742.149.549.5
R θJBJunction-to-board thermal resistance44.854.934.851.559.6
ψ JTJunction-to-top characterization parameter14.217.72717.86.9
ψ JBJunction-to-board characterization parameter44.554.434.751.259.1

74HC138 Typical Application

The SN74HC138 is useful as a scanning column selector for an LED Matrix display as it can be used for the low side drive of the LED string. The decoder functionality ensures that no more than one output is pulled to a low-level logic voltage so that only a single column is enabled at any point in time.

More datasheets

All Texas Instruments datasheets (2,442)

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