SN74LS155MEL

Overview

The SN74LS155MEL is a dual 2-line to 4-line decoder/demultiplexer manufactured by Texas Instruments, utilizing the LS-TTL logic family. It features two independent decoders with common address inputs and separate enable gates. The device operates at a nominal supply voltage of 5 V, with a maximum propagation delay of 30 ns and a maximum supply current of 10 mA. It is housed in a 16-pin ceramic DIP package.

Feature Summary

• Dual 1-of-4 decoder/demultiplexer architecture with shared address lines
• Schottky process technology for high-speed operation
• Input clamp diodes designed to limit high-speed termination effects

Applications

• Data demultiplexing circuits
• Address decoding systems
• Function generator applications

Procurement Notes

Verify the manufacturer designation carefully, as the SN74LS155 part number is primarily associated with Texas Instruments. Confirm that the MEL suffix corresponds to the specific military-grade or ceramic package variant required for your application. Ensure compatibility with existing LS-TTL logic levels and power supply requirements before procurement.

Selection Notes

Select this component when a dual decoder configuration with common addressing is required. It is suitable for designs needing Schottky TTL speed characteristics. Verify that the ceramic package and specific enable gate polarities (one active HIGH/LOW, one active LOW) match the system design constraints.

Part Context

This component belongs to the standard 74LS series of digital logic integrated circuits. It serves as a fundamental building block for sequential logic and data routing tasks within TTL-based digital systems, providing reliable switching capabilities for address selection and signal distribution.

Replacement Considerations

Compatible substitutes include the SN74LS155AD and other variants from the SN54/74LS155 family. Verify pinout compatibility and electrical specifications against the original datasheet before substitution.