The **M93C46-RMB3TP** is a 1-Kbit low-voltage serial Microwire EEPROM (Electrically Erasable Programmable Memory) manufactured by STMicroelectronics. It is commonly used in consumer electronics for storing configuration data, calibration parameters, and device IDs. --- ## 1. Technical Specifications Below are the key technical parameters for the M93C46-RMB3TP: | Parameter | Specification | | :--- | :--- | | **Memory Size** | 1 Kbit (1,024 bits) | | **Memory Organization** | Configurable: 64 x 16-bit or 128 x 8-bit | | **Interface** | Microwire (3-wire serial interface) | | **Supply Voltage (Vcc)** | 1.8V to 5.5V | | **Clock Frequency** | 2 MHz (at 4.5V - 5.5V) / 1 MHz (at 1.8V) | | **Operating Temperature** | -40°C to +125°C | | **Package Type** | SOT23-8 (RMB) | | **Write Cycles** | 4 million cycles (at 25°C) | | **Data Retention** | 200 Years | --- ## 2. Key Features and Functionality ### A. Memory Organization (ORG Pin) One of the most important features of this chip is the **ORG (Organization)** pin. - If ORG is tied to **Vcc**, the memory is organized as **64 words of 16 bits** each. - If ORG is tied to **VSS (Ground)**, the memory is organized as **128 words of 8 bits** each. ### B. Microwire Interface The device communicates using a standard serial peripheral interface called Microwire, which utilizes four signals: 1. **S (Chip Select):** Activates the device. 2. **C (Serial Clock):** Synchronizes data transfer. 3. **D (Serial Data Input):** Receives instructions and data. 4. **Q (Serial Data Output):** Sends data back to the microcontroller. ### C. Low Power Consumption The "R" in the part number signifies a low-voltage variant (1.8V to 5.5V). This makes it ideal for battery-powered devices where energy efficiency is critical. --- ## 3. Part Number Breakdown Understanding the suffix codes: - **M93C46**: Base part family (1 Kbit Microwire EEPROM). - **-R**: Indicates a wide supply voltage range (1.8V to 5.5V). - **MB**: Designates the package (SOT23-8, also known as UFDFPN8 in some contexts). - **3**: Indicates an Operating Temperature range of -40 to +125°C. - **TP**: Indicates Tape & Reel packaging. --- ## 4. Typical Application Circuit When integrating this component into a design, pull-up/pull-down resistors are often used on the Chip Select and Data lines to ensure stable states during power-up. ```c // Example Pseudocode for Reading a 16-bit word // 1. Set S (Chip Select) HIGH // 2. Send Start Bit (1) via D (Data In) // 3. Send Opcode (10 for READ) // 4. Send Address (6 bits for 64x16 mode) // 5. Read 16 bits from Q (Data Out) // 6. Set S (Chip Select) LOW ```