IC 74LS138 1 To 8 Decoder Demultiplexer

AED 8.30



The 74LS138 is a versatile decoder designed for high-performance applications in memory-decoding or data routing. With three binary select inputs and three enable inputs, it efficiently selects one of eight lines. Its compact size and faster speed make it a reliable choice for various devices.



  • Propagation Delay: Very short times for quick response.
  • Output: Always in TTL, ensuring compatibility with other TTL devices and microcontrollers.
  • Size: Compact design with a smaller footprint.
  • Speed: Much faster speed for enhanced reliability.



  • Technology Family: LS
  • Rating: Catalog
  • Supply Voltage: 1.0V to 5.5V
  • Frequency at Nominal Voltage: 35 MHz
  • Propagation Delay: 21nS (Typical)
  • Low Power Consumption: 32mW
  • Operating Temperature: -40°C to +125°C
  • ESD Protection
  • Balanced Propagation Delays
  • Specifically Designed for High Speed
  • Configuration: 3:8
  • Product Type: Standard


74LS138 Pinout:

Pin No Pin Name Description
1 A0 Address Input Pin A0
2 A1 Address Input Pin A1
3 A2 Address Input Pin A2
4 E1′ Active Low Enable Input E1′
5 E2′ Active Low Enable Input E2′
6 E3 Active high Enable Input E3
7 O7′ Active Low Output pin O7
8 GND Ground Pin
9 O6′ Active Low Output pin O6
10 O5′ Active Low Output pin O5
11 O4′ Active Low Output pin O4
12 O3′ Active Low Output pin O3
13 O2′ Active Low Output pin O2
14 O1′ Active Low Output pin O1
15 O0′ Active Low Output pin O0
16 Vcc Chip Supply Voltage



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