SN74LS298D

Overview

The SN74LS298D is a quadruple 2-input multiplexer with storage, belonging to the Texas Instruments 74LS logic series. It integrates four independent multiplexers, each featuring a storage register accessible via parallel load or serial shift capabilities. The device operates within a supply voltage range of 4.75 V to 5.25 V and supports a propagation delay of 32 ns at 5 V with 15 pF load capacitance. Designed for through-hole mounting, it utilizes a 14-pin SOIC-Narrow package. The component functions as a universal shift/store unit, allowing data to be stored in registers and shifted serially or loaded in parallel.

Feature Summary

• Integrates four independent 2-input multiplexers with dedicated storage registers
• Supports both parallel loading and serial shifting of data into storage elements
• Features open-collector outputs suitable for wired-OR configurations
• Operates within standard TTL logic levels using Low-power Schottky technology

Applications

• Universal shift and store register circuits
• Data routing and selection in digital systems
• Serial-to-parallel and parallel-to-serial conversion interfaces
• Multiplexed signal processing applications

Procurement Notes

Verify the specific suffix 'D' confirms the SOIC-Narrow 14-pin surface-mount package variant rather than the PDIP plastic DIP version. Confirm RoHS compliance status as LS series components may vary by manufacturing date code. Ensure the source document explicitly lists SN74LS298D to distinguish from the generic SN74LS298 family which includes multiple package options. Cross-reference the manufacturer part number against official Texas Instruments databases to validate authenticity and current production status.

Selection Notes

Select this component when a design requires multiple independent 2:1 multiplexing channels with integrated data storage capabilities. The open-collector output structure necessitates external pull-up resistors for proper high-level voltage generation. Consider the 74LS series speed and power characteristics relative to system requirements. Verify that the SOIC-Narrow package dimensions fit the available PCB footprint constraints compared to through-hole alternatives.

Part Context

This device is part of the broader 74LS (Low-power Schottky) logic family, known for improved switching speed over standard TTL while maintaining lower power consumption. The SN74LS298 specifically addresses applications requiring flexible data path management with storage. It complements other 74LS logic gates by providing complex sequential and combinational functionality in a single integrated circuit package.

Replacement Considerations

The SN74LS399 serves as a functional equivalent offering similar quadruple 2-input multiplexer with storage architecture. Other compatible variants include the HD74LS298 from Hitachi and the MC74LS298 from Motorola. Verify pinout compatibility and electrical specifications before substituting.