X1286
Real Time Clock/Calendar/CPU Supervisor with EEPROM
Typical Diagram
Key Features
- Real Time Clock/Calendar
- Tracks time in Hours, Minutes, Seconds and Hundredths of a Second
- Day of the Week, Day, Month, and Year
- 2 Polled Alarms (Non-volatile)
- Settable on the Second, Minute, Hour, Day of the Week, Day, or Month
- Repeat Mode (periodic interrupts)
- Oscillator Compensation on chip
- Internal feedback resistor and compensation capacitors
- 64 position Digitally Controlled Trim Capacitor
- 6 digital frequency adjustment settings to ±30ppm
- Battery Switch or Super Cap Input
- 32K x 8 Bits of EEPROM
- 128-Byte Page Write Mode
- 8 modes of Block Lock™ Protection
- Single Byte Write Capability
- High Reliability
- Data Retention: 100 years
- Endurance: 100,000 cycles per byte
- 2-Wire™ Interface interoperable with I2C*
- 400kHz data transfer rate
- Frequency Output (SW Selectable: Off, 1Hz, 100Hz, or 32.768kHz)
- Low Power CMOS
- 1.25µA Operating Current (Typical)
- Small Package Options
- 8 Ld EIAJ SOIC and 14 Ld TSSOP
- Repetitive Alarms
- Temperature Compensation
Description
The X1286 device is a Real Time Clock with clock/calendar, two polled alarms with integrated 32kx8 EEPROM, oscillator compensation, and battery backup switch.
The oscillator uses an external, low-cost 32.768kHz crystal. All compensation and trim components are integrated on the chip. This eliminates several external discrete components and a trim capacitor, saving board area and component cost.
The Real-Time Clock keeps track of time with separate registers for Hours, Minutes, Seconds and 1/100 of a second. The Calendar has separate registers for Date, Month, Year and Day-of-week. The calendar is correct through 2099, with automatic leap year correction.
The powerful Dual Alarms can be set to any Clock/Calendar value for a match. For instance, every minute, every Tuesday, or 5:23 AM on March 21. The alarms can be polled in the Status Register or provide a hardware interrupt (IRQ Pin). There is a repeat mode for the alarms allowing a periodic interrupt.
The PHZ/IRQ pin may be software selected to provide a frequency output of 1 Hz, 100 Hz, or 32,768 Hz.
The device offers a backup power input pin. This VBACK pin allows the device to be backed up by battery or SuperCap. The entire X1286 device is fully operational from 2.7 to 5.5 volts and the clock/calendar portion of the X1286 device remains fully operational down to 1.8 volts (Standby Mode).
The X1286 device provides 256K bits of EEPROM with 8 modes of BlockLock™ control. The BlockLock allows a safe, secure memory for critical user and configuration data, while allowing a large user storage area.
Applications
- Utility Meters
- HVAC Equipment
- Audio/Video Components
- Set Top Box/Television
- Modems
- Network Routers, Hubs, Switches, Bridges
- Cellular Infrastructure Equipment
- Fixed Broadband Wireless Equipment
- Pagers/PDA
- POS Equipment
- Test Meters/Fixtures
- Office Automation (Copiers, Fax)
- Home Appliances
- Computer Products
- Other Industrial/Medical/Automotive
