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 I_off. The I_off circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down.