The **M95080-RDS3** is a specific variant of the 8-Kbit serial SPI (Serial Peripheral Interface) EEPROM manufactured by STMicroelectronics. This component is widely used in automotive and industrial applications due to its reliability and low power consumption. --- ## 1. Key Technical Specifications The table below summarizes the core hardware parameters of the M95080-RDS3: | Parameter | Specification | | :--- | :--- | | **Memory Size** | 8 Kbits (1,024 x 8 bits) | | **Interface** | SPI (Serial Peripheral Interface) | | **Operating Voltage ($V_{CC}$)** | 1.8V to 5.5V | | **Max Clock Frequency** | 5 MHz (at 1.8V) to 20 MHz (at 4.5V+) | | **Package Type** | TSSOP8 (indicated by the 'S' in the suffix) | | **Temperature Range** | -40°C to +125°C (Automotive Grade 1) | | **Write Cycles** | 4 Million cycles (at 25°C) | | **Data Retention** | 200 Years | --- ## 2. Part Number Breakdown Understanding the specific suffix **RDS3** is crucial for component sourcing: * **M95080**: Base part number for the 8-Kbit SPI EEPROM family. * **R**: Operating voltage range (1.8V to 5.5V). * **D**: Denotes additional identification page (a 32-byte lockable page). * **S**: Package type (TSSOP8, 169 mil width). * **3**: Temperature range (Grade 3: -40 to +125°C), often compliant with automotive standards. --- ## 3. Functional Pinout The device typically uses an 8-pin configuration: | Pin | Symbol | Function | | :--- | :--- | :--- | | 1 | **S#** | Chip Select (Active Low) | | 2 | **Q** | Serial Data Output (MISO) | | 3 | **W#** | Write Protect (Active Low) | | 4 | **$V_{SS}$** | Ground | | 5 | **D** | Serial Data Input (MOSI) | | 6 | **C** | Serial Clock | | 7 | **HOLD#** | Pause Serial Communication | | 8 | **$V_{CC}$** | Supply Voltage | --- ## 4. Operational Features ### SPI Protocol Modes The device supports SPI modes **0** (0,0) and **3** (1,1). Data is latched on the rising edge of the clock (C) and shifted out on the falling edge. ### Memory Protection - **Status Register:** Contains a Write Enable Latch (WEL) bit and Block Protect (BP0, BP1) bits. - **Hardware Protection:** The **W#** pin can be used to freeze the Status Register, preventing accidental writes to the memory. - **Software Protection:** Specific areas of the memory array (1/4, 1/2, or the whole array) can be designated as Read-Only via register settings. ### Write Operations The device features a **32-byte Page Write** buffer. A single write instruction can update up to 32 bytes of data simultaneously, provided they reside on the same memory page. --- ## 5. Typical Applications * **Automotive:** Storing calibration data, odometer readings, or error codes in ECUs. * **Industrial:** Parameter storage for sensors and motor controllers. * **Consumer Electronics:** Storing configuration settings and user preferences.