text.skipToContent text.skipToNavigation


1-of-8 Decoder


Package | PIN: DBQ | 16
Temp: I (-40 to 85)
Carrier: Cut Tape
Qty Price
1-9 $1.51
10-24 $1.35
25-99 $1.26
100-249 $1.10
250-499 $1.01
500-749 $0.85
750-999 $0.70
1000+ $0.64


  • Function, Pinout, and Drive Compatible With FCT and F Logic
  • Reduced VOH (Typically = 3.3 V) Versions of Equivalent FCT Functions
  • Edge-Rate Control Circuitry for Significantly Improved Noise Characteristics
  • Ioff Supports Partial-Power-Down Mode Operation
  • Matched Rise and Fall Times
  • Fully Compatible With TTL Input and Output Logic Levels
  • Dual 1-of-8 Decoder With Enables
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 200-V Machine Model (A115-A)
    • 1000-V Charged-Device Model (C101)
  • CY54FCT138T
    • 32-mA Output Sink Current
    • 12-mA Output Source Current
  • CY74FCT138T
    • 64-mA Output Sink Current
    • 32-mA Output Source Current

Texas Instruments  CY74FCT138ATQCT

The \x92FCT138T devices are 1-of-8 decoders. These devices accept three binary weighted inputs (A0, A1, A2) and, when enabled, provide eight mutually exclusive active-low outputs (O\0\x96O\7). The \x92FCT138T devices feature three enable inputs: two active low (E\1, E\2) and one active high (E3 ).

All outputs are high unless E\1 and E\2 are low and E3 is high. This multiple-enable function allows easy parallel expansion of the device to a 1-of-32 (five lines to 32 lines) decoder with just four \x92FCT138T devices and one inverter.

These devices are fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down.