74LCX646MTCX

Buffers, Drivers, Receivers, Transceivers Overview

The Fairchild Semiconductor 74LCX646MTCX is a low-voltage octal bus transceiver from the 74LCX logic family. It features eight non-inverting data paths with 5V tolerant inputs and outputs, enabling direct interfacing between 3.3V systems and legacy 5V devices. The device operates within a supply voltage range of 2.0V to 3.6V and supports surface-mount TSSOP-48 packaging. Key electrical specifications include a maximum propagation delay of 5.2ns at VCC=3.3V with 50pF load, and output drive currents of ±24mA. It functions as both a transceiver and register, controlled by direction (DIR) and output enable (OE) signals.

Buffers, Drivers, Receivers, Transceivers Feature Summary

• Provides bidirectional data transfer for eight-bit wide buses with simultaneous register capability
• Features 5V tolerant inputs and outputs for seamless compatibility between 3.3V and 5V logic domains
• Includes independent direction control and output enable pins for flexible bus management

Buffers, Drivers, Receivers, Transceivers Applications

• Memory mapping in embedded systems
• I/O expansion for microcontrollers
• Bidirectional level shifting between 3.3V and 5V subsystems

Buffers, Drivers, Receivers, Transceivers Procurement Notes

Verify the manufacturer origin, as onsemi acquired Fairchild Semiconductor's logic business. Confirm the package type is TSSOP-48 and check for RoHS compliance status. Ensure the DIR and OE pin configurations match your schematic requirements before ordering.

Buffers, Drivers, Receivers, Transceivers Selection Notes

Select this component when an 8-bit wide bidirectional interface is required with mixed voltage levels. It is suitable for applications needing high-speed data transfer with low power consumption. Consider the TSSOP-48 footprint constraints and thermal performance during PCB layout.

Buffers, Drivers, Receivers, Transceivers Part Context

This part belongs to the 74LCX series, designed for low-voltage CMOS applications. It replaces older 74HC or 74HCT counterparts where lower voltage operation and 5V tolerance are critical. The device integrates buffer/register functionality to stabilize data on bidirectional buses.

Buffers, Drivers, Receivers, Transceivers Replacement Considerations

Direct substitutes include the 74LCX646MTC without the X suffix, or equivalent parts from other manufacturers such as NXP or TI within the same LCX family. Verify pin compatibility and electrical characteristics before substitution.