54F189DC

Overview

The MM54F189DC is a high-speed ECL 16-bit static RAM manufactured by National Semiconductor. It features a 16x4 organization with asynchronous operation and 3-state outputs. The device utilizes a ceramic dual in-line package (DIP) with 16 pins. It operates within an extended military temperature range of -55 °C to 125 °C. The maximum access time is specified at 650 ns. The component is not RoHS compliant and uses the JESD-30 code R-XDIP-T16 for its rectangular, in-line form factor.

Feature Summary

• High-speed ECL technology for rapid data processing
• Asynchronous memory operation mode
• Three-state output capability for bus interfacing
• Extended temperature range suitable for harsh environments

Applications

• Military aerospace systems requiring radiation-hardened or high-reliability memory
• High-performance computing applications utilizing ECL logic families
• Test and measurement equipment operating in extreme temperatures

Procurement Notes

Verify the specific suffix 'DC' against the manufacturer's official datasheet to confirm the ceramic DIP package and lead finish specifications. Ensure that the non-RoHS status aligns with project compliance requirements. Confirm availability through authorized distributors as this is a legacy component. Validate the 650 ns access time requirement against system timing constraints before procurement.

Selection Notes

Select this component when ECL speed is critical and the system architecture supports negative voltage supplies typical of ECL logic. The ceramic package provides superior thermal and mechanical stability compared to plastic variants. Consider the 3-state outputs if multiple memory devices share a common data bus. Verify that the -55 °C to 125 °C operating range meets the environmental conditions of the target application.

Part Context

This part belongs to the National Semiconductor 54F series of high-speed ECL memories. The 54F designation indicates military-grade performance and extended temperature ranges. It is distinct from the commercial 74F series. The SRAM type offers random access capabilities without the need for refreshing, unlike dynamic RAM technologies.

Replacement Considerations

Check for direct pin-compatible equivalents from Texas Instruments, which acquired National Semiconductor. Verify if other manufacturers offer ECL SRAMs with similar 650 ns access times and ceramic DIP packaging. Ensure voltage supply levels match the specific ECL standard used in the design.