MC74ACT640MELG

Overview

The MC74ACT640MELG is an octal bus transceiver from the onsemi ACT logic series, housed in a 20-lead SOIC package. It operates within a supply voltage range of 4.5 V to 5.5 V and supports input levels compatible with TTL standards while providing CMOS output levels. The device features three-state outputs and delivers maximum high-level and low-level output currents of -24 mA and 24 mA, respectively. Propagation delay is specified at 9 ns under a 50 pF load condition. It functions reliably across an industrial temperature range from -40 °C to +85 °C.

Feature Summary

• Octal configuration providing eight independent bidirectional data paths for efficient bus interfacing.
• Three-state output capability enabling direct connection to system buses without additional drivers.
• TTL-compatible input thresholds ensuring reliable signal recognition across standard logic families.

Applications

• High-speed data acquisition systems requiring robust signal transmission.
• Memory module interfaces utilizing parallel data pathways.
• Industrial control units managing multiple peripheral devices via shared buses.

Procurement Notes

Verify the specific suffix ELG against official datasheets to confirm package dimensions and tape-and-reel specifications. Ensure compatibility with existing PCB footprints by checking the SOIC-20 outline drawings. Confirm RoHS compliance status through current manufacturer documentation before finalizing procurement orders.

Selection Notes

Select this component when designing circuits requiring high-speed octal buffering with TTL input compatibility. The ACT series offers superior speed compared to standard 74LS counterparts. Verify that the operating voltage remains strictly within the 4.5 V to 5.5 V window to maintain signal integrity and prevent device damage during operation.

Part Context

This part belongs to the 74ACT family of high-speed CMOS logic devices manufactured by onsemi. The 74ACT640 specifically serves as an octal buffer and line driver. It is designed to replace older 74LS equivalents in modern applications where faster switching speeds and lower power consumption are required for digital signal processing tasks.

Replacement Considerations

The MC74ACT640NG is a documented pin-compatible alternative offering identical logical functionality in a 20-PDIP package. Verify package type requirements before substitution to ensure mechanical fit within the target assembly.