## Technical Overview of the M24C64-R The **M24C64-R** is a 64-Kbit (8192 x 8 bits) Serial I²C Bus EEPROM (Electrically Erasable Programmable Memory) manufactured primarily by STMicroelectronics. It is designed for low-voltage applications, often found in consumer electronics, industrial sensors, and medical devices. --- ### 1. Key Technical Specifications | Parameter | Value/Range | | :--- | :--- | | **Memory Size** | 64 Kbits (8 KB) | | **Interface** | I²C (Two-Wire) | | **Supply Voltage (Vcc)** | 1.8V to 5.5V | | **Clock Frequency** | 400 kHz (Fast Mode) or 1 MHz (Fast Mode Plus) | | **Write Cycles** | More than 4 million cycles | | **Data Retention** | Over 200 years | | **Package Options** | SO8, TSSOP8, UFDFPN8, WLCSP | --- ### 2. Functional Pins Description The M24C64-R typically utilizes an 8-pin layout. Below is the standard pinout functionality: 1. **E0, E1, E2 (Address Inputs):** Used to set the hardware chip address. This allows up to 8 similar devices to be connected to the same I²C bus. 2. **SDA (Serial Data):** Bi-directional pin used to transfer data into and out of the device. 3. **SCL (Serial Clock):** Used to synchronize the data transfer. 4. **WC (Write Control):** A hardware protection pin. If connected to $V_{CC}$, write operations are inhibited (Read-only mode). If connected to $V_{SS}$ (Ground), write operations are allowed. 5. **Vcc/Vss:** Power supply and Ground pins. --- ### 3. Core Features * **Byte and Page Write:** Supports writing a single byte or a full page of 32 bytes in one cycle. * **Random and Sequential Read:** Data can be accessed from a specific address or read continuously across the entire memory array. * **Low Power Consumption:** * Active Read current: < 2 mA. * Standby current: < 1 µA (at 1.8V). * **Enhanced Software Protection:** Includes a "Device Select Code" that must match the hardware address pins for the device to respond. --- ### 4. Application Circuit Example To interface the M24C64-R with a microcontroller (like an Arduino or STM32), pull-up resistors are required on the SDA and SCL lines. ```cpp // Example: Basic I2C Address calculation // Device Code (1010) + Hardware Pins (E2, E1, E0) + R/W Bit // If E0, E1, E2 are grounded: #define EEPROM_I2C_ADDRESS 0x50 ``` ---