The 74F138 is a 1-of-8 decoder/demultiplexer produced by Philips Semiconductors. It has demultiplexing capability, multiple input enable function, and is ideal for memory chip select decoding.
The Philips 74F138 is a 1-of-8 decoder/demultiplexer designed for applications such as memory chip select decoding. It accepts three binary weighted inputs (A0, A1, A2) and, when enabled, provides eight mutually exclusive, active low outputs (Q0 – Q7). The device features three enable inputs: two active low (E0, E1) and one active high (E2), allowing for easy parallel expansion to a 1-of-32 decoder.
| Supply Voltage (VCC) | 4.5V to 5.5V |
|---|---|
| Operating Temperature (Commercial) | 0°C to +70°C |
| Operating Temperature (Industrial) | -40°C to +85°C |
| Typical Propagation Delay | 5.8ns |
The device features three enable inputs: two active low (E0, E1) and one active high (E2).
It can be expanded to a 1-of-32 decoder using four 74F138s and one inverter.
The typical supply current is 13mA.