74LCX543MSA

Overview

The onsemi 74LCX543MSA is a low voltage octal registered transceiver featuring 5V tolerant inputs and outputs. It operates within a VCC range of 2.3V to 3.6V, utilizing advanced CMOS technology for high-speed performance with low power dissipation. The device contains two sets of D-type registers for data storage in either direction. Key electrical specifications include a maximum propagation delay of 7.0 ns at VCC = 3.3V, a maximum quiescent supply current of 10 µA, and an output drive capability of ±24 mA at VCC = 3.0V. It supports live insertion and withdrawal when configured correctly.

Feature Summary

• Provides 5V tolerance on both input and output pins, enabling safe interfacing between low voltage logic and 5V signal environments.
• Contains dual sets of D-type latches with independent Latch Enable and Output Enable controls for each register set.
• Implements patented noise and EMI reduction circuitry to minimize electromagnetic interference during operation.
• Supports live insertion and withdrawal capabilities, allowing hot-swapping functionality when output enables are properly managed.

Applications

• Interfacing low voltage microprocessors with 5V peripheral devices
• Data bus buffering in systems requiring bidirectional data flow control
• Memory interface circuits where temporary data storage is required

Procurement Notes

Verify the package type matches the specific suffix code; MSA indicates a 24-lead Shrink Small Outline Package (SSOP). Confirm that the ordering code includes the correct suffix if tape and reel packaging is required, which involves appending the letter 'X'. Ensure compatibility with the intended operating temperature range of -40°C to +85°C. Check that unused inputs are tied to defined logic levels to prevent floating states. Validate that the supplier provides documentation confirming the component meets the specified absolute maximum ratings.

Selection Notes

Select this component when bidirectional data transfer between 2.5V or 3.3V domains and 5V environments is necessary. The integrated latching mechanism allows for precise timing control of data flow compared to simple transceivers. Consider the 24-lead SSOP package constraints regarding board space and thermal management. Evaluate the need for separate enable controls for input and output buffers to manage bus contention effectively in complex system architectures.

Part Context

This part belongs to the LCX family of low voltage CMOS logic devices manufactured by Fairchild Semiconductor, now associated with onsemi. The LCX series is designed specifically for applications requiring operation at lower supply voltages while maintaining compatibility with legacy 5V systems. The 74LCX543 variant specifically addresses the need for registered data transmission with high impedance states during power transitions.

Replacement Considerations

Equivalent parts include the 74LCX543WM in SOIC packaging and the 74LCX543MTC in TSSOP packaging from the same manufacturer line. Verify pinout compatibility and electrical characteristics before substituting packages. Ensure that any replacement maintains the 5V tolerance specification and similar propagation delays for timing integrity.