RM25C64C-LSNI-T Equivalent & Substitute Parts

Part Overview

The RM25C64C-LSNI-T is a 64Kbit CBRAM (Conductive Bridging RAM) non-volatile memory IC manufactured by Renesas Electronics Corporation. This device operates via SPI interface at 10 MHz and is housed in an 8-SOIC surface mount package. The part is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support, design updates, and production continuity.

Substiute Parts

RM25C64C-LSNI-T

Renesas Electronics CorporationIn Stock: 684RM25C64C-LSNI-T Datasheet

Current PartRFQ

25AA640AT-I/SN

Microchip TechnologyIn Stock: 321325AA640AT-I/SN Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RM25C64C-LSNI-T is determined by the following critical parameters:

Memory Capacity & Interface: The substitute must provide 64Kbit storage capacity with SPI serial interface to maintain protocol compatibility with existing firmware and PCB designs.

Package Compatibility: The 8-SOIC (0.154", 3.90mm Width) surface mount package is mandatory for direct PCB footprint compatibility without layout redesign.

Operating Voltage Range: The substitute must operate within or encompass the original supply voltage specification of 1.65V ~ 3.6V to ensure reliable operation in the target application.

Clock Frequency: The 10 MHz SPI clock frequency requirement must be supported by the substitute device.

Temperature Range: The -40°C ~ 85°C operating temperature specification must be met or exceeded.

Non-Volatile Memory Type: The substitute must retain data without power, maintaining the non-volatile storage function of the original part.

The 25AA640AT-I/SN from Microchip Technology meets all substitution criteria. While the memory technology differs (EEPROM vs. CBRAM), both are non-volatile SPI-based 64Kbit memory devices in identical packages with compatible electrical specifications.

Parameter Comparison

Engineering Selection Recommendations

The 25AA640AT-I/SN is the qualified substitute for the obsolete RM25C64C-LSNI-T based on the following factors:

Product Status: The RM25C64C-LSNI-T is obsolete with limited inventory availability (618 Pcs). The 25AA640AT-I/SN is active in production with substantial inventory (3200 Pcs), ensuring long-term supply chain reliability.

Regulatory Compliance: Both parts are ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements.

Electrical Compatibility: The substitute operates within the original voltage specification range (1.8V ~ 5.5V encompasses 1.65V ~ 3.6V) and maintains identical operating temperature limits (-40°C ~ 85°C).

Package & Interface Equivalence: Identical 8-SOIC package and SPI interface enable direct substitution without PCB redesign or firmware protocol changes.

Programmability Verification: The 25AA640AT-I/SN is verified as programmable through DiGi-Electronics, confirming compatibility with standard programming equipment and procedures.

Frequently Asked Questions (FAQ)

Q: Can the 25AA640AT-I/SN be used as a direct replacement without PCB modifications?

A: Yes. Both parts use the identical 8-SOIC (0.154", 3.90mm Width) package with the same pinout and SPI interface, enabling direct PCB footprint compatibility without layout changes.

Q: What is the difference between CBRAM and EEPROM memory technologies?

A: CBRAM (Conductive Bridging RAM) and EEPROM are both non-volatile memory technologies. Both retain data without power and support SPI serial communication. The 25AA640AT-I/SN EEPROM provides equivalent functional performance for 64Kbit SPI memory applications.

Q: Are the supply voltage ranges compatible?

A: The RM25C64C-LSNI-T operates at 1.65V ~ 3.6V. The 25AA640AT-I/SN operates at 1.8V ~ 5.5V. The substitute's voltage range encompasses the original specification, ensuring compatibility in applications designed for the original part.

Q: What is the impact of different write cycle times?

A: The RM25C64C-LSNI-T specifies 100µs word write and 5ms page write times. The 25AA640AT-I/SN specifies 5ms page write time. For page-based write operations, both devices are equivalent. Applications requiring sub-millisecond word writes must evaluate timing requirements against the substitute's 5ms specification.

Q: Is the 25AA640AT-I/SN available in the same packaging options?

A: The 25AA640AT-I/SN is supplied in Cut Tape (CT) and Digi-Reel® packaging formats, both suitable for automated assembly processes equivalent to the original part's surface mount requirements.

Q: Are there any firmware or software changes required for substitution?

A: Both parts implement standard SPI protocol for 64Kbit memory access. No firmware modifications are required for basic read/write operations. Applications using device-specific features should review technical datasheets for any protocol differences.