DM74ALS157SJX

Overview

The DM74ALS157SJX is a Quad 2-Line to 1-Line Data Selector/Multiplexer manufactured by Fairchild Semiconductor. It belongs to the Advanced Low-power Schottky (ALS) logic family and operates within a standard TTL voltage range. The device features buffered inputs and outputs, providing full on-chip data selection for four output gates with a separate strobe input. It is housed in a 16-lead Small Outline Package (SOP), specifically JEDEC MS-013, with a width of 5.3mm. Typical propagation delay is 9 ns, and typical power dissipation is 49 mW.

Feature Summary

• Contains inverters and drivers to supply full on-chip data selection to four output gates
• Features buffered inputs and outputs for improved signal integrity
• Includes a separate strobe input for control functionality

Applications

• Data routing in microprocessor systems
• Memory address/data bus selection
• Asynchronous bidirectional data buses

Procurement Notes

Verify the specific suffix 'SJX' against official Fairchild or onsemi documentation to confirm package type and reel specifications. Ensure compatibility with existing board layouts requiring a 16-lead SOP (MS-013). Confirm lead-free status if required by project specifications.

Selection Notes

Select this component when a quad multiplexer with buffered I/O is required. The ALS series offers improved AC performance over LS counterparts. Verify that the 16-lead SOP footprint matches the PCB design constraints before finalizing the part number.

Part Context

This device is part of the DM74ALS157 family, which includes variants like DM74LS157. While sharing functional similarities, the ALS variant provides faster switching speeds and lower power consumption compared to standard LS logic families. It serves as a critical interface component for managing multiple data sources in digital circuits.

Replacement Considerations

DM74ALS157M

FAQ

What is the typical propagation delay for the DM74ALS157SJX?

The typical propagation delay time is 9 ns.

How many data inputs does the DM74ALS157SJX support?

It supports four independent 2-line to 1-line selectors, totaling eight data inputs.