DM74ALS646WMX

Overview

The DM74ALS646WMX is an octal 3-state bus transceiver and register manufactured by onsemi. It features a 24-lead SOIC package with a supply voltage range of 4.5V to 5.5V. The device operates within a temperature range of 0°C to +70°C. It includes independent registers for A and B buses, edge-triggered D-type flip-flops, and multiplexed real-time and stored data capabilities.

Feature Summary

• Octal 3-state bus transceiver with independent registers for A and B buses
• Multiplexed real-time and stored data transfer via SAB and SBA control pins
• Totem-pole outputs designed for driving highly-capacitive or low-impedance loads directly

Applications

• Buffer registers in bus-organized systems
• Bidirectional bus drivers
• I/O ports implementation
• Working registers for internal storage

Procurement Notes

Verify the suffix 'X' indicates tape and reel packaging as specified in the ordering code section. Confirm the manufacturer origin from Fairchild Semiconductor legacy documentation now under onsemi. Ensure the component meets RoHS requirements if applicable to your specific revision. Check for obsolescence status as this is a legacy logic family part.

Selection Notes

Select this component when an octal bidirectional bus interface with integrated storage is required. It supports direct connection to bus lines without pull-up components due to high-logic level drive. Consider the 3-state output capability for system isolation. Verify compatibility with TTL input levels and ALS logic family timing constraints.

Part Context

This device belongs to the 74ALS logic family, utilizing advanced oxide-isolated, ion-implanted Schottky TTL process. It combines bus transceiver functionality with dual octal D-type registers. The design allows for glitch-free switching between real-time and stored data modes using make-before-break select controls.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided source material.