25CS320T-H/ST

Overview

The Microchip Technology 25CS320-H/ST is a 32-Kbit (4,096 x 8 bit) Serial EEPROM utilizing an SPI-compatible bus. It features a 32-byte page size and supports byte or sequential reads and writes. The device operates within a voltage range of 1.7V to 5.5V, with clock frequencies up to 20 MHz at VCC ≥ 4.5V. It includes a Security Register with a preprogrammed 128-bit serial number and user-programmable ID space. Built-in ECC logic corrects single-bit errors per four-byte readout. The -H suffix denotes Extended temperature operation from -40°C to +150°C.

Feature Summary

• Integrated Error Correction Code (ECC) logic for data integrity
• Configurable Enhanced Write Protection with user-definable memory partitions
• Preprogrammed globally unique 128-bit serial number in the Security Register
• Programmable Undervoltage Lockout Detection (UVLO) threshold

Applications

• Automotive systems requiring AEC-Q100 qualification and high-temperature reliability
• Industrial control applications needing dependable nonvolatile memory storage
• Consumer electronics requiring component serialization and traceability

Procurement Notes

Verify that the ordering suffix matches the required specifications. The 'H' indicates Extended temperature range (-40°C to +150°C). The '/ST' indicates an 8-lead SOIC package. Confirm the specific revision level against the latest datasheet DS20006923B to ensure compatibility with system requirements.

Selection Notes

Select this component when high-temperature automotive or industrial environments are present, as indicated by the -H suffix. Ensure the host controller supports SPI Modes 0 or 3. Consider the Enhanced Write Protection mode if complex partition-based security is required over legacy block protection.

Part Context

The 25CS320 belongs to Microchip's 25CS series of Serial EEPROMs. It is backward compatible with devices such as the 25AA320A, 25LC320A, and AT25320B. The series is optimized for applications where reliable nonvolatile storage and device identification are critical.

Replacement Considerations

The datasheet confirms backward compatibility with the 25AA320A, 25LC320A, and AT25320B. Verify pinout and electrical characteristics match before substitution.

FAQ

What is the function of the HOLD pin?

The HOLD pin pauses serial communication without resetting the sequence, allowing the host to service higher priority interrupts while ignoring input transitions except for Chip Select.

How does the built-in ECC logic operate?

The ECC scheme can correct up to one incorrectly read bit within a four-byte readout and sets a flag in the STATUS register to report detected corrections.