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25AA040A

MCHP25AA040A

Microchip Technology
Low-cost SPI serial EEPROM alternative for simple nonvolatile storage when FRAM endurance and speed are not required
NRND7,739 in stock
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Overview

The 25AA040A is a 4 Kbit SPI serial EEPROM from Microchip Technology, organized as 512 bytes of 8 bits each. It operates over a wide voltage range of 1.8V to 5.5V and supports clock frequencies up to 10 MHz, making it suitable for low-power and battery-operated embedded systems. This memory device is designed for reliable nonvolatile storage with features like 16-byte page writing and block write protection.

Why Choose This Part

This EEPROM offers a balance of reliability and flexibility with 1,000,000 erase/write cycles and over 200 years of data retention. Its SPI interface and 10 MHz clock support faster data access than standard I2C EEPROMs, while the 1.8V minimum supply voltage ensures compatibility with modern low-voltage microcontrollers.

Applications

Configuration Storage
Storing calibration data, device settings, and user preferences in industrial or consumer electronics.
Lookup Tables
Holding character maps for small displays or linearization tables for sensor data.
Event Logging
Recording error codes or historical status updates in low-frequency logging applications where high endurance is not required.
Boot Parameters
Storing boot addresses or system configuration flags for microcontrollers during startup.

Key Specifications

Technology EEPROM
Memory Size 4Kbit
Memory Type Non-Volatile
Memory Format EEPROM
Mounting Type Surface Mount
Package / Case SOT-23-6
Clock Frequency 10 MHz
Memory Interface SPI
Voltage - Supply 1.8V ~ 5.5V
Memory Organization 512 x 8
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package SOT-23-6
Write Cycle Time - Word, Page 5ms

Getting Started

To interface with the 25AA040A, use a standard SPI master with Mode 0 or Mode 3 configuration. Ensure the WP (Write Protect) pin is tied to VCC if hardware write protection is not needed, and remember to check the Status Register after a write operation to confirm the 5ms internal cycle is complete. Many Microchip PIC and AVR development boards provide sample C libraries for standard 25-series SPI EEPROMs.

Also Consider

25LC040A MCHPMicrochip Technology - Select this version if the system requires a 2.5V minimum operating voltage with potentially higher clock speeds up to 10 MHz depending on the variant.
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