New Features
Repetitive Alarms &
Temperature Compensation
4K (512 x 8)
X1226
Real Time Clock/Calendar with EEPROM
2-Wire
™
RTC
FEATURES
• Real Time Clock/Calendar
—Tracks time in Hours, Minutes, and Seconds
—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
• 512 x 8 Bits of EEPROM
—64-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,
4096Hz or 32.768kHz)
• Low Power CMOS
—1.25µA Operating Current (Typical)
• Small Package Options
—8-Lead SOIC and 8-Lead TSSOP
BLOCK DIAGRAM
OSC
Compensation
X1
Frequency
Divider
APPLICATIONS
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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
DESCRIPTION
The X1226 device is a Real Time Clock with clock/
calendar, two polled alarms with integrated 512x8
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.
32.768kHz
X2
Oscillator
1Hz
Timer
Calendar
Logic
Time
Keeping
Registers
(SRAM)
Battery
Switch
Circuitry
V
CC
V
BACK
PHZ/IRQ
Select
Status
Registers
(SRAM)
Mask
SCL
SDA
Serial
Interface
Decoder
Control
Decode
Logic
Control/
Registers
(EEPROM)
Alarm
Compare
Alarm Regs
(EEPROM)
4K
EEPROM
ARRAY
8
*I2C is a Trademark of Philips.
REV 1.1.24 1/13/03
www.xicor.com
Characteristics subject to change without notice.
1 of 24
XICOR [ XICOR INC. ]
