MC74ACT240N

Overview

The MC74ACT240N is an octal buffer and line driver manufactured by onsemi, belonging to the 74ACT logic series. It features eight inverting outputs with three-state capability, designed for memory address driving, clock distribution, and bus-oriented transmission applications. The device operates within a supply voltage range of 4.5V to 5.5V and utilizes a 20-pin DIP package. Key electrical characteristics include TTL-compatible inputs and output drive currents of 24mA sourcing and sinking. The component supports industrial operating temperatures ranging from -40°C to +85°C.

Feature Summary

• Octal configuration providing eight independent inverting buffers or line drivers within a single integrated circuit.
• Three-state output architecture enables direct connection to bus systems without external switching hardware.
• TTL-compatible input thresholds allow seamless interfacing with standard TTL logic families.
• High current drive capability supports direct loading of bus lines and memory address registers.

Applications

• Memory address driver circuits
• Clock signal distribution networks
• Bus-oriented transmitter and receiver interfaces

Procurement Notes

Verify component authenticity through authorized distributors due to potential availability of obsolete or refurbished units. Confirm RoHS compliance status as older production runs may not meet current environmental regulations. Validate pinout compatibility with target PCB footprints before integration. Check datasheet revisions for any parameter updates that may affect system performance.

Selection Notes

Select this component when requiring high-drive octal buffering with TTL input compatibility in a through-hole package. Consider alternative packages such as SOIC or TSSOP if surface mount technology is preferred. Ensure supply voltage constraints align with the 4.5V to 5.5V operational range. Evaluate thermal requirements against the specified industrial temperature limits for long-term reliability.

Part Context

This part belongs to the widely adopted 74AC/ACT logic family, known for balanced speed and power consumption. The ACT variant specifically bridges CMOS performance with TTL input levels, facilitating mixed-logic system designs. As an octal buffer, it consolidates multiple discrete gates into a single package, reducing board space and interconnect complexity compared to individual gate solutions.

Replacement Considerations

Public confirmed substitute part numbers include CD74AC240E and SN74AC240N from Texas Instruments. These alternatives offer parameter-equivalent functionality but belong to the AC series rather than ACT. Verify input threshold compatibility differences between AC and ACT logic families before substitution.