TC74LCX540FT(EL)

Overview

The TC74LCX540FT(EL) is a low-voltage octal bus buffer manufactured by Toshiba. It features inverted, three-state outputs and supports 5-V tolerant inputs and outputs. The device operates within a power supply voltage range of 1.65 V to 3.6 V. It achieves high-speed operation with a maximum propagation delay of 6.5 ns at 3.0 V to 3.6 V. The component provides a minimum output current of 24 mA at 3.0 V. It includes power-down protection on all inputs and outputs and offers static discharge protection for all input lines.

Feature Summary

• Provides high-speed signal buffering with inverted logic functionality in a low-voltage CMOS architecture.
• Features five-volt tolerant inputs and outputs, enabling safe interfacing between 3.3-V systems and 5-V environments.
• Includes dual active-low output enables that place terminal outputs into a high-impedance state when asserted high.
• Integrates power-down protection circuits on all inputs and outputs to prevent excessive current draw during power-off states.

Applications

• Used as a memory address driver in three-state memory systems.
• Interfaces 3.3-V system components with 5-V supply environments.
• Functions as an octal bus buffer for data routing applications.

Procurement Notes

Verify the specific package variant, as the LCX540 series is available in SOP and VSSOP formats. Confirm RoHS compliance status directly with the manufacturer or authorized distributors. Ensure the design accounts for the specified operating temperature range of -40°C to +85°C. Review the absolute maximum ratings carefully to avoid exceeding voltage limits on inputs or outputs relative to the power supply.

Selection Notes

Select this component when designing systems requiring octal buffering with inverted polarity and three-state control. It is suitable for applications needing compatibility with standard 74-series pinouts while operating at lower voltages. Consider the 6.5 ns propagation delay and 24 mA drive capability for timing and load requirements. Verify that the 5-V tolerance feature meets the interface needs between different voltage domains.

Part Context

This part belongs to the TC74LCX540 family of low-voltage CMOS digital integrated circuits. It is functionally compatible with various 74-series types, including AC, VHC, HC, F, ALS, and LS variants. The device utilizes silicon gate and double-layer metal wiring C2MOS technology to achieve performance levels similar to bipolar Schottky TTL while maintaining low power dissipation characteristics typical of CMOS devices.

Replacement Considerations

Functionally equivalent parts include the TC74AC540 and TC74HC540 from Toshiba. Other manufacturers may offer compatible octal bus buffers with inverted outputs and three-state capabilities. Verify voltage ranges and pinout compatibility before substitution.