5 VOLT PC REAL TIME CLOCK The **M48T86MH1** is a **Timekeeping RAM (TKRAM)** device manufactured by **STMicroelectronics (ST)**. Below are its key specifications, descriptions, and features:
### **Specifications:**
- **Type:** Real-Time Clock (RTC) with SRAM
- **Memory Size:** 8KB (8,192 bytes)
- **Interface:** Parallel (8-bit)
- **Supply Voltage:** 4.5V to 5.5V
- **Operating Temperature Range:** -40°C to +85°C
- **Package:** 28-pin DIP (Dual In-line Package)
- **Battery Backup:** Built-in lithium energy source (retains data for over 10 years)
### **Descriptions:**
- The **M48T86MH1** integrates a **real-time clock (RTC)**, **calendar**, and **SRAM** in a single chip.
- It maintains timekeeping functions (seconds, minutes, hours, day, date, month, year) with leap-year compensation.
- Includes **power-fail detection** and **write protection** to prevent data corruption.
### **Features:**
- **Real-Time Clock (RTC):**
- Counts seconds, minutes, hours, day, date, month, and year (with leap-year correction).
- 12-hour or 24-hour format selectable.
- **Non-Volatile SRAM:**
- 8KB of battery-backed SRAM for data retention.
- **Low Power Consumption:**
- Operates in battery backup mode when main power fails.
- **Century Byte Support:**
- Includes a century register for Y2K compliance.
- **Power-Fail Detection:**
- Monitors VCC and switches to battery backup automatically.
- **Write Protection:**
- Prevents accidental writes to critical registers.
This device is commonly used in **embedded systems, industrial controls, and computing applications** requiring reliable timekeeping and non-volatile memory.
