70121S55JG

Memory IC Overview

The Renesas Electronics Corporation 70121S55JG is a high-speed, asynchronous dual-port static random-access memory (SRAM) integrated circuit. It features a storage capacity of 18 kilobits organized as 2K words by 9 bits per word. The device supports parallel interface operation with a maximum access time of 55 nanoseconds. It operates on a single 5V power supply within the voltage range of 4.5V to 5.5V. The component is housed in a 52-pin Plastic Leadless Chip Carrier (PLCC) package designed for surface-mount installation. It functions as a master dual-port RAM capable of expanding data bus width when paired with slave devices.

Memory IC Feature Summary

• Supports fully asynchronous independent operation from either port without external logic requirements
• Includes on-chip hardware arbitration logic and semaphore signaling for efficient port-to-port communication
• Enables expansion of data bus width to 18 bits or more through master/slave configuration with compatible slave chips
• Features automatic power-down mode controlled by chip enable signals for low standby power consumption

Memory IC Applications

• High-speed data buffering in telecommunications equipment
• Network switch and router memory architectures
• Industrial control systems requiring fast dual-port data exchange
• Embedded systems needing simultaneous independent access to shared memory resources

Memory IC Procurement Notes

Verify component authenticity and physical integrity upon receipt, as this part is officially discontinued. Confirm that the specific suffix matches the required package and temperature grade specifications. Check for moisture sensitivity level compliance and appropriate handling procedures during assembly. Ensure compatibility with existing board designs regarding pinout and electrical characteristics before implementation.

Memory IC Selection Notes

Select this component for applications requiring true dual-port memory with independent address and data buses. It is suitable for systems needing high-speed data transfer between two processors or controllers. Consider the 55ns access speed and 5V operating voltage for compatibility with legacy TTL logic families. Evaluate the 52-pin PLCC package constraints against available PCB real estate and mounting requirements.

Memory IC Part Context

This device belongs to the IDT/Renesas 70121 series of dual-port SRAMs. It is designed to operate as a master unit in multi-chip configurations. The series provides non-volatile-like performance with volatile memory speed. It replaces older discrete logic solutions for bus arbitration in wide-memory systems.

Memory IC Replacement Considerations

Consult official manufacturer documentation for verified replacement part numbers. No direct substitutes are confirmed in the provided source material.