SN74AS257DRE4 Quad 2-Input Multiplexer from Texas Instruments

The SN74AS257DRE4 by Texas Instruments is a high-performance, quad 2-input multiplexer that features four identical 2-input multiplexers with 3-state outputs. Designed to operate from a wide range of supply voltages, this multiplexer can handle inputs from 4.5V to 5.5V, making it versatile for various digital logic applications. It is particularly suitable for implementing noninverting data selectors and multiplexers with full on-chip binary decoding to select the desired data source.

The SN74AS257DRE4 offers a fast propagation delay, typically 3.5 ns, which is crucial for high-speed operations. Its low power consumption and high noise immunity are characteristics of the advanced Schottky (AS) high-speed CMOS technology used in its manufacturing. This makes it an excellent choice for interfacing with high-speed microprocessors and for applications requiring high-speed data flow and manipulation.

The device comes in a small-outline package with a 16-pin configuration, designated by the DRE suffix, and is characterized for operation from 0°C to 70°C. Its compact form factor is ideal for densely packed PCB layouts where space is at a premium.

Each multiplexer has two inputs (A and B), one output (Y), and a common select input (S). The output state is controlled by the select input: when the select input is low, the A input is connected to the output, and when high, the B input is connected. The 3-state outputs can be connected directly to a bus-organized system. They can be placed in a high-impedance state (off) by applying a high logic level to the output enable (OE) pin, allowing for bus line sharing without the need for external components.

Features of the SN74AS257DRE4 include the ability to drive bus lines or buffer memory address registers, and its outputs can interface with TTL logic levels. This makes it a flexible solution for a wide range of digital logic circuits. The multiplexer's high-performance attributes, reliability, and ease of use make it a preferred choice for designers and engineers in the electronics industry.

For more detailed information, including the complete specifications, truth tables, and physical dimensions, please refer to the official Texas Instruments datasheet for the SN74AS257DRE4.