MC74LCX245MELG

Overview

The MC74LCX245MELG is a low-voltage CMOS octal bidirectional transceiver manufactured by onsemi. It operates within a supply voltage range of 2.0 V to 5.5 V and features 5 V tolerant inputs and outputs, enabling safe interfacing with 5 V devices even when the device supply is lower. The component provides non-inverting data transfer controlled by Transmit/Receive and Output Enable signals. It offers balanced 24 mA source and sink current capabilities at both A and B ports, ensuring robust signal driving for bus-oriented applications.

Feature Summary

• Provides bidirectional data transfer between two 8-bit buses using a single direction control input.
• Features 5 V tolerant I/Os allowing direct interface with 5 V logic systems while operating at lower voltages.
• Includes an IOFF specification to guarantee high-impedance states during power-off to prevent back-driving.
• Supports live insertion and withdrawal without causing system damage or data corruption.

Applications

• Memory address and data bus driving in embedded systems
• Bus-oriented communication interfaces requiring level shifting
• Low-voltage to 5 V TTL logic interconnection circuits

Procurement Notes

Verify the specific suffix MELG corresponds to the SOIC-20 lead-free package configuration. Confirm that the procurement channel sources genuine onsemi components to ensure compliance with the specified electrical characteristics and moisture sensitivity levels. Check for any automotive qualification requirements if the application demands AEC-Q100 standards, as standard commercial parts may differ from NLV prefixed variants.

Selection Notes

Select this component when designing systems requiring bidirectional data flow between mixed voltage domains, specifically where 2.0 V to 3.6 V logic must interface with 5 V peripherals. The 5 V tolerance eliminates the need for external level shifters. Ensure the design accounts for the 24 mA drive capability and verify that the PCB layout supports the thermal dissipation requirements for the SOIC-20 package under maximum load conditions.

Part Context

This part belongs to the MC74LCX245 series of low-voltage CMOS octal transceivers. It is functionally compatible with other industry-standard octal bus transceivers but is distinguished by its specific 5 V tolerance and low-voltage operation range. The series is designed for high-performance applications requiring minimal static power consumption and robust noise immunity in digital bus architectures.

Replacement Considerations

Direct substitutes include MC74LCX245DT and MC74LCX245DWR2G from onsemi. Cross-manufacturer equivalents such as TC74LCX245F from Toshiba are also documented as similar alternatives. Verify pinout compatibility and electrical specifications before substitution.