The **M93C86-RMB3P/S** is a specific variant of the 16-Kbit serial Microwire EEPROM (Electrically Erasable Programmable Read-Only Memory) manufactured by STMicroelectronics. It is commonly used for parameter storage in automotive and industrial applications. --- ## 1. Technical Specifications Below are the primary electrical and physical characteristics of this specific part number. | Feature | Specification | | :--- | :--- | | **Memory Size** | 16 Kbit (2048 x 8 bits or 1024 x 16 bits) | | **Interface** | Microwire (3-Wire Serial) | | **Operating Voltage** | 1.8V to 5.5V | | **Clock Frequency** | 2 MHz (at 4.5V - 5.5V) | | **Package Type** | UFDFPN8 (MLP8) - 2x3 mm | | **Temperature Range** | -40°C to +125°C (Automotive Grade 3) | | **Write Cycles** | 4 Million cycles | | **Data Retention** | 200 Years | --- ## 2. Part Number Breakdown Understanding the suffix codes helps identify the specific constraints of the component: * **M93C86**: Base part number for the 16-Kbit Microwire EEPROM. * **-R**: Indicates the device operates at a low voltage range (**1.8V to 5.5V**). * **MB**: Designates the package type **UFDFPN8** (Ultra-thin Fine pitch Dual Flat No-lead, 2x3mm). * **3**: Temperature range suffix for **-40 to +125 °C**. * **P/S**: Packing and Lead-free status (typically Tape & Reel with RoHS compliance). --- ## 3. Key Operational Features The device is designed for high-reliability environments. Key features include: ### Organizational Flexibility The device features a "Sequential Read" mode and a user-selectable organization via the **ORG pin**: * If ORG is connected to $V_{CC}$, it is organized as **1024 x 16 bits**. * If ORG is connected to $V_{SS}$ (GND), it is organized as **2048 x 8 bits**. ### Write Protection To prevent accidental data corruption, the chip includes a **Write Enable (WEN)** and **Write Disable (WDS)** instruction set. The device powers up in a "Write Disabled" state to ensure data integrity during power fluctuations. ### Enhanced Durability Unlike standard consumer EEPROMs, the "3" grade (Automotive) ensures the part can withstand extreme thermal cycling and high-vibration environments found in Engine Control Units (ECUs) or sensor modules. --- ## 4. Typical Connection Diagram | Pin Number | Name | Function | | :--- | :--- | :--- | | 1 | S | Chip Select | | 2 | C | Serial Clock | | 3 | D | Serial Data Input | | 4 | Q | Serial Data Output | | 5 | Vss | Ground | | 6 | ORG | Internal Organization (x8 or x16) | | 7 | DU | Don't Use (Leave floating) | | 8 | Vcc | Supply Voltage |