74HC7540D,112

Overview

The Nexperia 74HC7540D,112 is an octal Schmitt trigger buffer and line driver featuring inverting outputs and three-state capability. It operates within a supply voltage range of 2.0 V to 6.0 V and supports ambient temperatures from -40 °C to +125 °C. The device utilizes the SO20 plastic small outline package (SOT163-1). Key electrical parameters include a propagation delay of up to 36 ns at 6.0 V with a 50 pF load, high-level output current of -7.8 mA, and low-level output current of 7.8 mA. Static supply current reaches a maximum of 160 μA.

Feature Summary

• Incorporates Schmitt trigger inputs to transform slowly changing signals into sharply defined jitter-free outputs.
• Features dual active-low output enable inputs (OE1 and OE2) for flexible bus management.
• Includes input clamp diodes allowing interface to voltages exceeding VCC using current limiting resistors.

Applications

• High-noise immunity signal buffering
• Line driving applications requiring inverting logic
• Bus-oriented systems utilizing 3-state control

Procurement Notes

Verify the specific ordering suffix '112' corresponds to the tube packaging configuration as indicated by distributor data. Confirm that the SO20 package variant matches the SOT163-1 mechanical drawing requirements. Ensure design compliance with the specified absolute maximum ratings to prevent permanent damage during operation.

Selection Notes

Select this component when designing circuits requiring eight-channel inversion with noise filtering capabilities. The wide supply voltage range accommodates various logic families. Verify that the required propagation delay fits within the system timing constraints under the intended operating temperature and load capacitance conditions.

Part Context

This part belongs to the 74HC series of CMOS logic devices manufactured by Nexperia. It serves as an octal version of single or dual Schmitt trigger buffers, providing enhanced noise immunity compared to standard logic gates. The device is designed for general-purpose digital applications requiring robust signal integrity across industrial temperature ranges.

Replacement Considerations

The 74HC7540D,118 is a verified substitute offering identical functionality but packaged in tape and reel format instead of tubes.

FAQ

How does the device handle input signals exceeding the supply voltage?

The inputs include clamp diodes, which allow the use of current-limiting resistors to safely interface inputs to voltages higher than VCC.

What is the function of the OE1 and OE2 pins?

These are active-low output enable inputs. A HIGH level on either pin forces all outputs into a high-impedance OFF-state.