The **M93C86-RMB6** is an 16-Kbit serial Microwire EEPROM (Electrically Erasable Programmable Read-Only Memory) manufactured by STMicroelectronics. It is commonly used for non-volatile data storage in consumer electronics, automotive systems, and industrial controls. --- ### ## Technical Specifications The following table summarizes the core electrical and physical characteristics of the M93C86-RMB6: | Parameter | Specification | | :--- | :--- | | **Memory Size** | 16 Kbit (16,384 bits) | | **Organization** | User-selectable: 2048 x 8 bits OR 1024 x 16 bits | | **Interface** | Microwire (3-wire serial interface) | | **Operating Voltage (Vcc)** | 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 | | **Operating Temperature** | -40°C to +85°C (Industrial Grade 6) | | **Write Cycles** | 4 million cycles (at 25°C) | | **Data Retention** | 200 Years | --- ### ### Key Electronic Components & Features 1. **Memory Array (EEPROM Cells):** The core of the device consists of floating-gate transistors. These cells retain data even after power is removed. The M93C86 allows for byte-wide (x8) or word-wide (x16) organization depending on the logic state of the "ORG" pin. 2. **Microwire Bus Interface:** Unlike I2C or SPI, Microwire uses a specific three-wire protocol: * **S (Chip Select):** Activates the device. * **C (Serial Clock):** Synchronizes data movement. * **D (Serial Data Input):** Receives opcodes, addresses, and data. * **Q (Serial Data Output):** Outputs data during read cycles. 3. **Instruction Decoder & Control Logic:** This internal logic interprets 8-bit opcodes sent from the microcontroller. Common commands include: * **READ:** Read data from memory. * **WEN (Write Enable):** Unlocks the memory for writing (security feature). * **WRITE:** Writes a single byte/word. * **WRAL:** Writes the same data to the entire memory array simultaneously. 4. **Self-Timed Programming Cycle:** The device includes an internal timer. Once a write command is received, the chip handles the high-voltage generation and timing required to "burn" the data into the cells without further intervention from the host MCU. --- ### ### Application Circuitry When integrating the M93C86-RMB6 into a PCB design, the following external electronic considerations are required: ```c // Typical Connection Schematic Logic MCU Pin (Digital Out) ----> S (Chip Select) MCU Pin (Clock Out) ----> C (Serial Clock) MCU Pin (Digital Out) ----> D (Data Input) MCU Pin (Digital In) <---- Q (Data Output) VCC (1.8V - 5.5V) ----> VCC (With 0.1uF Decoupling Capacitor) GND ----> VSS ``` --- ### ### Package Detail: UFDFPN8 The **"MB6"** suffix denotes the package and temperature grade. The UFDFPN8 is a miniature, leadless package measuring approximately 2x3mm. It is designed for high-density surface mount (SMT) applications where vertical space is limited.