512 BIT (64 X 8) SERIAL RTC WITH SUPERVISORY FUNCTIONS The M41ST84W is a serial real-time clock (RTC) manufactured by STMicroelectronics (ST). Below are the factual details about its specifications, descriptions, and features:
### **Specifications:**
1. **Interface:** I²C (Inter-Integrated Circuit) serial interface.
2. **Supply Voltage:** Operates from **2.0V to 5.5V**.
3. **Timekeeping Accuracy:** ±5 ppm (parts per million) at **25°C**.
4. **Clock Frequency:** 32.768 kHz.
5. **Operating Temperature Range:** **-40°C to +85°C**.
6. **Memory:**
- **56 bytes** of general-purpose SRAM.
- **8 bytes** of clock/calendar registers (BCD format).
7. **Battery Backup:** Supports an external battery for power backup.
8. **Low Power Consumption:**
- **400 nA** in battery backup mode (typical).
9. **Package:** **SO8N** (8-pin Small Outline package).
### **Descriptions:**
- The M41ST84W is a low-power serial RTC with an integrated **crystal oscillator**, eliminating the need for an external crystal.
- It provides **seconds, minutes, hours, day, date, month, and year** information with automatic leap-year compensation.
- Includes a **power-on reset** function to ensure proper initialization.
- Features a **programmable alarm** and **watchdog timer**.
### **Features:**
1. **I²C Serial Interface:** Supports standard (100 kHz) and fast (400 kHz) modes.
2. **Automatic Leap-Year Compensation:** Valid up to **2099**.
3. **Battery Switchover:** Seamless transition between main power and backup battery.
4. **Programmable Alarm:** Can trigger an interrupt output.
5. **Watchdog Timer:** Configurable timeout period.
6. **Power-On Reset:** Ensures correct initialization at startup.
7. **Industrial Temperature Range:** Suitable for harsh environments.
This information is based on the manufacturer's datasheet and technical documentation.
