MC74F640N

Overview

The MC74F640N is an octal buffer and line driver manufactured by onsemi, belonging to the 74F logic series. It features eight independent non-inverting buffers with three-state outputs, housed in a 20-pin DIP package. The device operates within a supply voltage range of 4.5V to 5.5V. Key electrical characteristics include a maximum propagation delay of 13ns at 5V with 50pF load, high output drive capability of 24mA for both high and low states, and input logic levels defined as 0.8V for low and 2V for high. It supports through-hole mounting and functions across an operating temperature range of -40°C to 85°C.

Feature Summary

• Provides eight independent non-inverting buffer channels with three-state output control for bus-oriented applications.
• Delivers high-speed performance characteristic of the 74F logic family with significant current drive capabilities.
• Features robust input protection and Schmitt-trigger-like noise immunity inherent to the F-series design.

Applications

• Clock buffering and distribution in digital systems
• Driving capacitive loads on data buses
• Interface between different logic families or voltage domains

Procurement Notes

Verify component authenticity and datasheet alignment due to potential legacy status. Confirm package pinout compatibility with existing PCB footprints. Check for RoHS compliance variations across manufacturing batches. Ensure storage conditions meet moisture sensitivity level requirements before reflow soldering processes.

Selection Notes

Select this component when high-speed switching and strong drive strength are required for octal bus applications. Compare against 74LS equivalents for speed improvements or 74HC variants for lower power consumption. Evaluate thermal management needs given the higher current drive capabilities compared to standard CMOS logic families.

Part Context

This part belongs to the widely adopted 74xx logic family, specifically the Fast (F) sub-family known for superior speed-performance-power product. The MC74F640N serves as a critical interface element in complex digital designs requiring signal isolation and amplification across multiple lines simultaneously.

Replacement Considerations

Direct substitutes include MC74F640AN and generic 74F640 equivalents from other manufacturers. Verify pin compatibility and electrical specifications match exactly. Consider 74FCT640 for faster transition times if system timing allows.