The MC74LS258BN is a Quad 2-Input Multiplexer with 3-State Outputs from the 74LS series, manufactured by Freescale Semiconductor (NXP). It features four independent 2-to-1 multiplexers, each with the added functionality of 3-state outputs. The 3-state outputs allow the device to be connected directly to a bus without loading it when the outputs are disabled. This is crucial in applications where multiple devices share the same data lines.

Applications

• Bus-Oriented Data Selection: Selecting data from one of two sources for transmission over a shared bus.
• Memory Address Decoding: Implementing memory address decoding schemes where multiple memory chips share the same address lines.
• Peripheral Device Selection: Selecting which peripheral device is allowed to communicate with the system.
• Data Routing and Switching: Routing data signals from one location to another within a digital system.
• Logic Function Generation: Implementing simple logic functions using the multiplexer and 3-state output capabilities.

Features

• Quad 2-Input Multiplexer: Contains four independent 2-to-1 multiplexers in a single package.
• 3-State Outputs: Allows the outputs to be disabled, placing them in a high-impedance state.
• Low-Power Schottky (LS) Technology: Offers a good balance between speed and power consumption.
• TTL Compatible: Interfaces easily with other TTL logic devices.
• Common Enable Input: A single enable input controls all four 3-state outputs.

Benefits

• Bus Compatibility: 3-state outputs allow the device to be directly connected to a bus without loading it when inactive.
• Efficient Data Selection: Provides a flexible way to select data from multiple sources.
• Simplified Circuit Design: Reduces component count and board space.
• Improved System Performance: Minimizes bus loading, leading to better overall system performance.
• Reduced Power Consumption: LS technology and the ability to disable the outputs contribute to lower power dissipation.

The 'BN' suffix typically indicates a DIP (Dual In-Line Package). The MC74LS258BN is a valuable component in bus-oriented systems where multiple devices share the same data lines. The 3-state outputs prevent bus contention and ensure reliable data transmission. The common enable input provides a convenient way to disable all four multiplexers simultaneously.