25LC320AT-I/ST

Overview

The Microchip Technology 25LC320AT-I/ST is a 32-Kbit (4096 x 8-bit) Serial Electrically Erasable PROM. It operates within a supply voltage range of 2.5V to 5.5V and supports a maximum clock frequency of 10 MHz at voltages between 4.5V and 5.5V. The device utilizes an SPI-compatible serial bus with separate data in (SI) and data out (SO) lines, controlled by Chip Select (CS), Serial Clock (SCK), and Hold (HOLD) inputs. It features a 32-byte page write buffer, self-timed erase/write cycles up to 5 ms, and block write protection for none, 1/4, 1/2, or all of the array. The component is housed in an 8-lead TSSOP package and is rated for industrial temperature ranges from -40°C to +85°C.

Feature Summary

• Supports high-speed SPI communication with a maximum clock frequency of 10 MHz.
• Includes hardware write protection via the WP pin and software control through the STATUS register.
• Features a 32-byte page write buffer to optimize sequential data writing operations.
• Provides power-on/off data protection circuitry and a write enable latch to prevent inadvertent writes.

Applications

• Microcontroller system data storage
• Configuration parameter retention
• Calibration value storage

Procurement Notes

Verify that the specific ordering suffix 'T' corresponds to tape-and-reel packaging as indicated by standard Microchip naming conventions for this series. Confirm the 'I' suffix matches the required industrial temperature range (-40°C to +85°C). Ensure the voltage requirements align with the 2.5V minimum specification for the 25LC320A variant, distinct from the 1.8V minimum of the 25AA320A. Cross-reference the datasheet revision DS20001828H for any recent package or electrical characteristic updates.

Selection Notes

Select this component when an SPI interface is required for non-volatile memory with a capacity of 32 Kbit. It is suitable for applications needing robust write protection mechanisms and high endurance (>1M cycles). Choose this part over the 25AA320A if the system supply voltage does not drop below 2.5V, as the 25LC320A offers higher speed performance at standard 5V logic levels. Consider the TSSOP package constraints for PCB layout.

Part Context

This device belongs to the 25XX320A family of 32-Kbit Serial EEPROMs manufactured by Microchip Technology. The family includes variants like the 25AA320A, which supports a lower voltage range starting at 1.8V. The 25LC320A specifically targets applications requiring operation from 2.5V to 5.5V. The 'T' suffix typically denotes tape-and-reel packaging, while 'I' indicates the industrial temperature grade. These devices are designed for direct interfacing with popular microcontroller families.

Replacement Considerations

The 25AA320AT-I/ST is a functional substitute within the same family, differing primarily in its wider operating voltage range (1.8V to 5.5V vs. 2.5V to 5.5V). Other compatible parts include the 25LC320A without the 'T' suffix for tube packaging. Verify voltage compatibility before substitution.