EEPROM Memory I2C Module AT24C256 SMD

Features:

• Large Storage Capacity: 32,768 bytes (256Kb) organized as 32,768 x 8 bits.
• Flexible Voltage Operation: Supports both low and standard voltage operations from 1.8V to 5.5V.
• Multiple Module Support: Adjustable I2C address via three jumpers enables up to 8 EEPROMs on the same I2C bus.
• Hardware Write Protection: Includes a write-protect pin to prevent accidental data overwrite.
• High Endurance: 1,000,000 write cycles and 40 years of data retention.
• Efficient Write Cycle: Self-timed 5ms max page write for 64 bytes (partial writes allowed).

Specifications:

• Chip: AT24C256
• Capacity: 256Kb (32,768 bytes)
• Organization: 32,768 x 8-bit
• Operating Voltage: 1.8V–5.5V
• I2C Speed:
  • 1 MHz @ 5V
  • 400 kHz @ 2.7V or 2.5V
  • 100 kHz @ 1.8V
• Write Cycle Time: 5 ms max (self-timed)
• Write Endurance: 1 million cycles
• Data Retention: 40 years
• Interface: I2C (2-wire)
• Dimensions: 6.00 x 6.00 x 1.00 cm

Pinout:

• VCC: Power supply (1.8V–5.5V)
• GND: Ground
• SCL: I2C Clock line
• SDA: I2C Data line
• WP: Write Protect (connect to GND to enable writing)

Wiring with Arduino:

Connect the EEPROM to Arduino using the I2C interface:

• VCC → 5V on Arduino
• GND → GND on Arduino
• SCL → A5 (for Uno/Nano)
• SDA → A4 (for Uno/Nano)

Example Arduino Code:

Make sure to install the AT24C256 library before using this code.

// I2C library
#include "AT24C256.h"

// Create EEPROM object
AT24C256 eeprom = AT24C256();

int val = 24;  // Value to store
int Add = 0;   // Memory address

void setup() {
  Serial.begin(9600);
  while (!Serial) {
    ; // Wait for Serial to connect (needed for native USB boards)
  }
}

void loop() {
  // Write value to EEPROM
  Serial.println("Writing of " + (String)val + " on " + (String)Add);
  eeprom.write(val, Add);

  // Read back and display the value
  Serial.println(eeprom.read(Add));

  // Stop further execution
  while(1);
}

Applications:

• Data logging and sensor value storage
• Settings backup for wireless systems
• Offline configuration memory
• EEPROM-based security keys