25CS320-E/SN

Overview

The Microchip Technology 25CS320-E/SN is a 32-Kbit (4,096 x 8 bit) Serial EEPROM utilizing SPI-compatible bus communication. It operates within a voltage range of 1.7V to 5.5V and supports clock frequencies up to 20 MHz at VCC ≥ 4.5V. The device features an 8-lead SOIC package and is rated for extended temperature operation from -40°C to +125°C. Key specifications include a maximum write current of 5.0 mA, standby current of 1.0 µA, and data retention exceeding 200 years.

Feature Summary

• Integrated Security Register containing a factory-programmed 128-bit serial number and user-programmable lockable ID page
• Built-in Error Correction Code (ECC) logic capable of correcting single-bit errors within four-byte readouts
• Configurable Enhanced Write Protection Mode allowing independent memory partitioning with unique protection behaviors
• Programmable Undervoltage Lockout Detection circuit to inhibit write sequences during brown-out events

Applications

• Automotive applications requiring AEC-Q100 qualified nonvolatile memory storage
• Industrial systems needing reliable data logging with enhanced write protection
• Consumer electronics requiring component serialization via unique serial numbers

Procurement Notes

Verify the specific ordering suffix matches the required package type and temperature grade. Confirm that the Extended temperature rating (-40°C to +125°C) aligns with system environmental constraints. Ensure compatibility with existing SPI host controllers regarding voltage levels and clock polarity phases before finalizing procurement orders.

Selection Notes

Select this component when application requirements demand integrated security features such as unique device identification and hardware-enforced write protection. The built-in ECC functionality makes it suitable for environments where data integrity is critical. Consider the extended temperature range if the operating environment exceeds standard industrial limits.

Part Context

The 25CS320 belongs to Microchip's 25CS series of Serial EEPROMs designed for high-reliability applications. This series distinguishes itself through advanced security registers and configurable write protection schemes not found in legacy counterparts. It serves as a backward-compatible upgrade for systems previously using 25AA320A or 25LC320A devices.

Replacement Considerations

The 25CS320 is backward compatible with the 25AA320A, 25LC320A, and AT25320B. When replacing these legacy parts, verify that the host controller supports the new Enhanced Write Protection mode configuration and that the pinout remains identical for direct socket replacement.

FAQ

How does the Enhanced Write Protection Mode differ from Legacy mode?

Legacy mode uses fixed block protection (quarter, half, or entire array), while Enhanced mode allows users to define independent memory partitions with unique protection behaviors for each segment.

What is the function of the built-in ECC logic?

The ECC logic detects and corrects up to one incorrectly read bit within a four-byte readout sequence, enhancing data reliability without external processing overhead.