74HCT7540D,118

Overview

The Nexperia 74HCT7540D,118 is an octal Schmitt trigger buffer and line driver featuring inverting outputs with three-state capability. It operates within a supply voltage range of 4.5 V to 5.5 V and utilizes the HCT logic family for TTL-compatible input levels. The device includes two active-low output enable inputs (OE1 and OE2) that force outputs into a high-impedance state when asserted. It is housed in a SO20 plastic small outline package (SOT163-1).

Feature Summary

• Schmitt-trigger inputs provide tolerance for slowly changing signals and ensure jitter-free output transitions.
• Dual independent output enables allow flexible control over the three-state high-impedance OFF-state.
• CMOS construction ensures low power dissipation while maintaining high noise immunity.

Applications

• Clock buffering and distribution in digital systems
• Driving long transmission lines or bus structures
• Interface circuits requiring signal regeneration

Procurement Notes

Verify the specific ordering suffix matches the required package variant. Confirm RoHS compliance status through official manufacturer documentation prior to integration. Ensure design specifications align with the absolute maximum ratings defined in the product data sheet to prevent device damage.

Selection Notes

Select this component when TTL-level compatibility is required alongside Schmitt-trigger noise immunity. The HCT series is appropriate for 5 V logic environments. Consider the HC variant if a wider supply voltage range or CMOS input levels are necessary instead.

Part Context

This part belongs to the 74HCT7540 logic family manufactured by Nexperia. It is functionally related to the 74HC7540 but differs in input threshold characteristics to support TTL interfacing. Both variants share identical pinouts and packaging options.

Replacement Considerations

The 74HC7540D serves as a functional alternative with CMOS input levels. Verify that the application can accommodate the different input voltage thresholds associated with the HC logic family before substitution.

FAQ

How does the device handle slow input signal transitions?

The integrated Schmitt-trigger inputs convert slowly changing signals into sharply defined output transitions, eliminating jitter.

What is the function of the OE1 and OE2 pins?

These are active-low output enable inputs. Asserting either pin forces all corresponding outputs into a high-impedance OFF-state.