The **M24M01-R** is a high-capacity serial EEPROM (Electrically Erasable Programmable Read-Only Memory) device developed by STMicroelectronics. It is widely used for non-volatile data storage in applications where power consumption and space are critical. --- ## 1. Core Technical Specifications The "M01" in the part number signifies its capacity, while the "R" indicates its specific voltage operating range. | Feature | Specification | | :--- | :--- | | **Memory Size** | 1 Megabit (1,024 Kb) | | **Organization** | 128K x 8 bits (131,072 bytes) | | **Interface** | I²C (Two-Wire Serial Interface) | | **Operating Voltage** | 1.8V to 5.5V | | **Clock Frequency** | 400 kHz (Fast-mode) / 1 MHz (Fast-mode Plus) | | **Write Cycles** | 4 million cycles (at 25°C) | | **Data Retention** | 200 years | | **Page Size** | 256 Bytes | --- ## 2. Pinout Configuration (8-Pin Packages) The M24M01-R is typically found in SO8, TSSOP8, or WLCSP packages. | Pin Name | Type | Description | | :--- | :--- | :--- | | **E2** | Input | Chip Enable (Used to define the device address) | | **SDA** | I/O | Serial Data (Bidirectional data transfer) | | **SCL** | Input | Serial Clock (Synchronizes data movement) | | **WC** | Input | Write Control (Hardware protection; if High, write ops are disabled) | | **Vcc** | Power | Supply Voltage (1.8V - 5.5V) | | **Vss** | Power | Ground (0V) | --- ## 3. Key Electronic Characteristics ### A. I²C Addressing Because it is a 1Mb device, it uses a specific addressing scheme. While standard I²C uses 7 bits, the M24M01-R utilizes a **Device Select Code** (`1010`) followed by an address bit (`E2`) and two memory page bits to navigate the 128KB of space. ### B. Low Power Consumption Designed for mobile and battery-operated devices: * **Write Current:** Max 2 mA (at 5V). * **Read Current:** Max 1 mA (at 400 kHz). * **Standby Current:** Max 5 μA (at 1.8V). ### C. Write Protection (WC Pin) The Write Control pin provides hardware-level security. When connected to $V_{CC}$, the entire memory contents become read-only, preventing accidental data corruption or unauthorized overwriting. --- ## 4. Common Use Cases * **Parameter Storage:** Storing calibration data and user settings in medical or industrial tools. * **Firmware Backup:** Holding small bootloader codes or configuration tables. * **Data Logging:** Recording sensor data in IoT devices where power must be conserved.