The **M93C66-RBN3P** is a specific type of Non-Volatile Memory (NVM) integrated circuit. It is part of the Microwire serial bus family, commonly used for storing configuration data, calibration parameters, or device IDs that must be retained even when power is removed. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Memory Size** | 4 Kbit (4096 bits) | | **Memory Organization** | 256 x 16-bit or 512 x 8-bit (Selectable) | | **Interface** | Microwire (3-wire serial) | | **Operating Voltage** | 1.8V to 5.5V | | **Clock Frequency** | 2 MHz (at 4.5V - 5.5V) | | **Package Type** | PDIP8 (Plastic Dual In-line Package, 8 pins) | | **Temperature Range** | -40°C to +125°C | --- ### 2. Pinout Configuration The device is housed in an 8-pin package. Below is the functional description of the pins: | Pin Number | Name | 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** | Internal Organization (High=x16, Low=x8) | | 7 | **DU** | Don't Use (Usually NC) | | 8 | **Vcc** | Supply Voltage | --- ### 3. Functional Features * **Write Protection:** The device includes a software-controlled write protection mechanism (Write Enable/Disable instructions) to prevent accidental data erasure. * **Sequential Read:** Data can be read out sequentially, meaning the address pointer increments automatically after each word is read. * **High Endurance:** It is rated for approximately **1 million write cycles** and has a data retention period of over **40 years**. * **Self-Timed Write Cycle:** Once a write command is sent, the chip manages the internal timing for burning the data into the cells (typically around 5ms). --- ### 4. Part Number Breakdown The suffix **-RBN3P** provides specific details about the variant: * **M93C66:** Base model (4K Microwire EEPROM). * **-R:** Operating voltage range (1.8V to 5.5V). * **BN:** Package type (PDIP8). * **3:** Temperature range (-40°C to +125°C). * **P:** RoHS compliant / Lead-free. --- ### 5. Application Code Example (Pseudo-code) To interact with the M93C66, a microcontroller must toggle the Clock and Data lines according to the Microwire protocol: ```cpp // Example: Basic logic to Read from Address void readEEPROM(uint16_t address) { digitalWrite(CHIP_SELECT, HIGH); send_bits(READ_OPCODE, 3); // Microwire READ command send_bits(address, 8); // Address to read uint16_t data = receive_bits(16); // Fetch 16-bit data digitalWrite(CHIP_SELECT, LOW); } ```