The **M95256-RBN3T** is a high-performance, 256-Kbit serial SPI (Serial Peripheral Interface) EEPROM manufactured by STMicroelectronics. It is designed for applications requiring non-volatile memory storage with high reliability and low power consumption. --- ### ## Technical Specifications | Parameter | Specification | | :--- | :--- | | **Memory Size** | 256 Kbits (32,768 x 8 bits) | | **Interface** | SPI (Mode 0 and Mode 3) | | **Max Clock Frequency** | 20 MHz (at 4.5V - 5.5V) / 5 MHz (at 1.8V) | | **Operating Voltage** | 1.8V to 5.5V | | **Operating Temperature** | -40°C to +125°C | | **Page Size** | 64 Bytes | | **Endurance** | 4 Million Write Cycles | | **Data Retention** | 200 Years | | **Package Type** | MSOP8 (TSSOP8) | --- ### ## Pin Configuration and Functions The device typically comes in an 8-pin package. Below is the standard functional mapping: | Pin Number | Name | Description | | :--- | :--- | :--- | | 1 | **S#** | Chip Select (Active Low) | | 2 | **Q** | Serial Data Output | | 3 | **W#** | Write Protect (Hardware protection) | | 4 | **VSS** | Ground | | 5 | **D** | Serial Data Input | | 6 | **C** | Serial Clock | | 7 | **HOLD#** | Pause Serial Communication | | 8 | **VCC** | Supply Voltage | --- ### ## Key Features 1. **High Endurance:** Capable of up to 4 million cycles, making it ideal for logging parameters that change frequently. 2. **Byte and Page Write:** Supports writing a single byte or a full page of 64 bytes. A page write cycle is typically completed in **5ms**. 3. **Hardware & Software Protection:** * The `W#` pin provides hardware write protection. * Software protection is managed via the **Status Register**, allowing the memory to be partitioned into "Write Protected" blocks (Quarter, Half, or Whole memory). 4. **Low Power Consumption:** * Active read current: < 2 mA. * Standby current: < 1 µA (Deep Power-down mode). --- ### ## Use Cases * **Automotive:** Storing calibration data and odometer readings. * **Industrial:** Configuration settings for PLCs or sensors. * **Consumer Electronics:** Firmware storage and user preference settings for devices like smart home hubs. ---