The **M93C86-RMB3TG/S** is a specific variant of a serial EEPROM (Electrically Erasable Programmable Read-Only Memory) chip manufactured by STMicroelectronics. It is commonly used for non-volatile data storage in automotive and industrial applications. --- ### 1. Key Technical Specifications Below is a breakdown of the primary technical parameters for this specific part number: | Parameter | Specification | | :--- | :--- | | **Memory Size** | 16 Kbit (2048 x 8 bits or 1024 x 16 bits) | | **Interface Type** | Microwire (3-wire serial interface) | | **Operating Voltage** | 1.8V to 5.5V | | **Clock Frequency** | 2 MHz (at 4.5V) / 1 MHz (at 1.8V) | | **Package Type** | UFDFPN8 (MLP8) - Ultra-thin Fine Pitch Dual Flat No-lead | | **Temperature Range** | -40°C to +125°C (Grade 3) | | **Endurance** | 4 million write cycles | | **Data Retention** | 200 years | --- ### 2. Part Number Breakdown The suffixing in the part number provides specific information regarding its packaging and grading: * **M93C86**: Base model (16 Kbit Microwire EEPROM). * **-R**: Operating voltage range (1.8V to 5.5V). * **MB**: Package code for UFDFPN8 (2x3 mm). * **3**: Temperature range 3 (-40 to +125 °C), typically used for high-reliability/automotive environments. * **TG**: Tape & Reel packing with RoHS compliant/Green materials. * **S**: Indicates specific process technology or manufacturing site distinction. --- ### 3. Pin Configuration (UFDFPN8) The device typically uses an 8-pin layout. The Microwire protocol requires specific signals to communicate with a microcontroller. | Pin Number | Name | Description | | :--- | :--- | :--- | | 1 | **S (CS)** | Chip Select | | 2 | **C (SK)** | Serial Clock | | 3 | **D (DI)** | Serial Data Input | | 4 | **Q (DO)** | Serial Data Output | | 5 | **Vss** | Ground | | 6 | **ORG** | Organization Select (x8 or x16 mode) | | 7 | **DU** | Don't Use / Internal Connection | | 8 | **Vcc** | Supply Voltage | --- ### 4. Implementation Example To interface with this chip using a microcontroller (e.g., an Arduino or STM32), you would implement the Microwire protocol, which is a precursor to SPI. ```cpp // Pseudocode for reading a word from M93C86 void readEEPROM(int address) { digitalWrite(CS_PIN, HIGH); // Start Communication sendInstruction(READ_OPCODE); // Send Read Opcode sendAddress(address); // Send Target Address int data = shiftIn(DATA_OUT); // Receive Data digitalWrite(CS_PIN, LOW); // End Communication } ``` --- ### 5. Notable Features * **Selectable Organization:** By pulling the **ORG** pin High or Low, the user can choose whether the 16Kb memory is treated as 2048 bytes or 1024 16-bit words. * **Write Protection:** Includes software-based write protection instructions (WEN/WDS) to prevent accidental data corruption. * **Self-Timed Programming:** The chip handles the internal erase/write timing, so the MCU doesn't need to manage high-voltage pulses.