MC74HC640AFEL

Overview

The MC74HC640AFEL is an 8-bit bus transceiver featuring inverted outputs and a 3-state interface. Manufactured by Motorola (now NXP/onsemi), it operates within a supply voltage range of 2V to 6V. The device supports bidirectional data transfer with common control for output enable and direction. It is housed in a small outline package with 20 terminals, designed for CMOS logic applications requiring high noise immunity and low power consumption.

Feature Summary

• Provides bidirectional data transmission between two buses with inverted logic levels
• Features three-state outputs to isolate the bus when disabled
• Utilizes common control signals for simultaneous direction and output enable management

Applications

• Memory module data bus interfacing
• Microprocessor system address and data routing
• Bidirectional gate drivers for digital communication lines

Procurement Notes

Verify the manufacturer origin carefully, as production rights transferred from Motorola to NXP and subsequently onsemi. Confirm the specific suffix indicates the correct package variant and lead-free status. Ensure the component matches the required operating temperature range and voltage specifications for your design environment before finalizing procurement.

Selection Notes

Select this component when an 8-bit inverting transceiver with 3-state capability is required. It is suitable for systems operating between 2V and 6V. Consider the SOP-20 package constraints and ensure compatibility with the target logic family voltage levels. Verify that the inverted output polarity aligns with the downstream circuit requirements.

Part Context

This part belongs to the 74HC series of high-speed CMOS logic devices. It serves as a standard interface solution for connecting microprocessors to memory or peripheral devices. The device maintains compatibility with previous 74LS logic families while offering improved speed and lower power consumption typical of HC technology.

Replacement Considerations

The MC74HC640DWD is a documented alternative from the same manufacturer family. Other compatible parts include variants from Renesas such as the HD74HCT640FP-EL, though voltage thresholds may differ due to HCT vs HC logic standards.