The **M93C56-RBN3P** is a specific type of non-volatile memory chip manufactured by **STMicroelectronics**. It belongs to the Microwire serial EEPROM family, commonly used for storing configuration data, calibration parameters, and small amounts of user data in embedded systems. --- ## 1. Technical Specifications The part number "M93C56-RBN3P" reveals specific details about its architecture and operating environment: | Feature | Specification | | :--- | :--- | | **Memory Size** | 2 Kbit (256 x 8 bits or 128 x 16 bits) | | **Interface** | Microwire (Serial 3-Wire) | | **Operating Voltage** | 1.8V to 5.5V | | **Clock Frequency** | 2 MHz (at 5V) | | **Package Type** | PDIP8 (Plastic Dual In-line Package, 8 pins) | | **Temperature Range** | -40°C to +125°C (Automotive Grade 3) | | **Write Cycles** | Up to 1 million (Endurance) | | **Data Retention** | 40 Years | --- ## 2. Pinout Configuration The device is housed in an 8-pin DIP package. The pin functions are standardized for the Microwire protocol: | Pin Number | Symbol | Description | | :--- | :--- | :--- | | 1 | **S** | Chip Select (Active High) | | 2 | **C** | Serial Clock | | 3 | **D** | Serial Data Input | | 4 | **Q** | Serial Data Output | | 5 | **Vss** | Ground | | 6 | **ORG** | Organization Select (x8 or x16 mode) | | 7 | **DU** | Don't Use (Must be left floating or grounded) | | 8 | **Vcc** | Supply Voltage | --- ## 3. Key Electronic Characteristics ### Organization (ORG Pin) One of the most important features of this chip is the **ORG pin**. - If ORG is connected to **Vcc**, the memory is organized as **128 words of 16 bits**. - If ORG is connected to **Vss (Ground)**, the memory is organized as **256 bytes of 8 bits**. ### Write Protection The device includes a "Write Enable" instruction that must be sent before any data can be written to the memory. This prevents accidental data corruption due to noise or power fluctuations. ### Sequential Read The M93C56 supports sequential reading, meaning after the first address is accessed, the chip can continue outputting the next data bits automatically as long as the clock continues and Chip Select remains high. --- ## 4. Typical Application Circuit When connecting this to a microcontroller (like an Arduino or STM32), the wiring usually looks like this: ```cpp // Schematic Logic Connection: // MCU Pin (MOSI) ---> Pin 3 (D) // MCU Pin (MISO) <--- Pin 4 (Q) // MCU Pin (SCK) ---> Pin 2 (C) // MCU Pin (GPIO) ---> Pin 1 (S) ``` ---