TC74LCX540FT(ELK,M

Overview

The TC74LCX540FT(ELK,M) is a low-voltage octal bus buffer with inverted outputs and 5-V tolerant inputs/outputs. It operates at VCC from 1.65 to 3.6 V, achieving a maximum propagation delay of 6.5 ns at 3.0 to 3.6 V. The device provides an output current of 24 mA (min) at 3.0 V and features two active-low output enables. It includes power-down protection on all inputs and outputs, ensuring high-impedance states when disabled.

Feature Summary

• Features 5-V tolerant inputs and outputs for interfacing between 3.3-V systems and 5-V environments.
• Provides power-down protection on all inputs and outputs to prevent unwanted current flow during power-off states.
• Includes two active-low output enables that place terminal outputs in a high-impedance state when asserted high.

Applications

• Used as a 3-state memory address driver.
• Interfaces low-voltage logic circuits with 5-V supply environments.
• Functions as an inverting octal bus buffer in 3.3-V system architectures.

Procurement Notes

Verify the specific manufacturing date code against datasheet notes regarding electrical characteristics, as parameters for 1.8 V operation apply only to units manufactured from January 2009 onward. Confirm package type availability, as the component is offered in both SOP and VSSOP formats with distinct physical dimensions.

Selection Notes

Select this component for applications requiring bidirectional data transfer with inversion in low-voltage environments. Ensure the design accommodates the specified 5-V tolerance on input and output pins. Verify that the required propagation delay meets the 6.5 ns maximum limit under the target operating voltage conditions.

Part Context

This part belongs to the TC74LCX series of CMOS digital integrated circuits. It is functionally compatible with various 74-series logic types, including AC, VHC, HC, F, ALS, and LS families. The device utilizes silicon gate and double-layer metal wiring CMOS technology to achieve high-speed performance while maintaining low power dissipation.

Replacement Considerations

Direct substitutes include other 74LCX540 variants from Toshiba or pin-compatible alternatives from manufacturers like Nexperia or ON Semiconductor. Ensure replacement parts match the 5-V tolerant specification and the specific package footprint if transitioning between SOP and VSSOP.

FAQ

What is the behavior of the outputs when either 1OE or 2OE is high?

When either 1OE or 2OE is high, the terminal outputs enter a high-impedance state, effectively disconnecting them from the circuit.

Does the device provide protection against static discharge?

Yes, all inputs are equipped with protection circuits designed to handle static discharge events.