74HCT240D,653

Overview

The Nexperia 74HCT240D,653 is an octal buffer and line driver featuring inverting 3-state outputs. It operates within a supply voltage range of 4.5 V to 5.5 V. The device provides two independent output enables (1OE and 2OE), each controlling four outputs. Inputs include clamp diodes for interfacing with voltages exceeding VCC. Propagation delay is typically 11 ns at 4.5 V with a 15 pF load.

Feature Summary

• Inverting 3-state outputs controlled by two separate enable inputs
• TTL input levels compatible with standard logic families
• Input clamp diodes allow direct interface to voltages above VCC

Applications

• Memory address drivers
• Clock drivers
• Bus-oriented transmissions

Procurement Notes

Verify the specific ordering suffix against current Nexperia documentation to confirm package type and temperature range. Confirm RoHS compliance status and REACH registration details prior to procurement. Ensure design-in compatibility with existing system voltage levels and signal integrity requirements.

Selection Notes

Select this component when TTL-compatible input thresholds are required alongside CMOS drive capabilities. The dual enable structure allows flexible bus configuration. Verify that the SOIC-20 package dimensions fit the target PCB layout constraints and thermal dissipation needs.

Part Context

This part belongs to the 74HCT logic family, designed for high-speed operation with TTL-compatible inputs. It serves as a replacement for older 74S240 or 74LS240 devices where lower power consumption and higher speed are needed. The D package denotes the standard plastic small outline variant.

Replacement Considerations

Direct pin-compatible replacements include the 74HC240D for CMOS input levels. Cross-reference with other manufacturers' 74HCT240 equivalents ensuring identical pinout and electrical specifications.