The **M9356-RDS6T** (often identified as part of the STMicroelectronics M93 family) is a Serial Microwire (3-wire) EEPROM (Electrically Erasable Programmable Read-Only Memory). These components are widely used for non-volatile parameter storage in automotive and industrial applications. --- ### 1. Key Technical Specifications Below are the core electronic characteristics of the device: | Feature | Specification | | :--- | :--- | | **Memory Size** | 2 Kbit (organized as 128 x 16-bit or 256 x 8-bit) | | **Interface** | Microwire (Serial 3-Wire) | | **Operating Voltage** | 1.8V to 5.5V | | **Clock Frequency** | Up to 2 MHz (at 4.5V - 5.5V) | | **Package Type** | TSSOP8 (Thin Shrink Small Outline Package) | | **Operating Temp** | -40°C to +85°C (Standard Industrial Grade) | | **Write Cycles** | More than 4 million cycles | | **Data Retention** | Over 200 years | --- ### 2. Pin Configuration (TSSOP8) The device typically follows a standard 8-pin layout for Microwire EEPROMs: 1. **S (Chip Select):** High level enables the device; low level puts it in standby. 2. **C (Serial Clock):** Used to synchronize data transfer. 3. **D (Serial Data Input):** Receives instructions and data. 4. **Q (Serial Data Output):** Outputs data during read operations. 5. **VSS:** Ground. 6. **ORG (Organization):** Selects between x8 or x16 memory organization. 7. **DU/NC:** Don't Use or No Connect. 8. **VCC:** Supply Voltage. --- ### 3. Functional Features * **Sequential Read:** Allows reading the entire memory contents via a single command. * **Write Protection:** Includes a "Write Disable" state at power-on to prevent accidental data corruption. * **Ready/Busy Signal:** During a write cycle, the Data Output (Q) pin can be used to poll the status of the internal write operation. * **Low Power Consumption:** Features a standby mode that draws minimal current when Chip Select is low. --- ### 4. Code Example (Pseudo-Logic) If you were interfacing this with a microcontroller (like an Arduino or STM32), the communication logic follows this structure: ```cpp // Example: Sending a READ instruction to M9356 void readEEPROM(int address) { digitalWrite(CHIP_SELECT, HIGH); // Start communication shiftOut(DATA_IN, CLOCK, MSBFIRST, READ_OPCODE); // Send Opcode shiftOut(DATA_IN, CLOCK, MSBFIRST, address); // Send Address uint16_t data = shiftIn(DATA_OUT, CLOCK, MSBFIRST); // Read 16-bit word digitalWrite(CHIP_SELECT, LOW); // End communication } ``` ---