1
®
FN8099.2
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774
| Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2005-2006. All Rights Reserved
*I
2
C is a Trademark of Philips. All other trademarks mentioned are the property of their respective owners.
X1227
2-Wire
™
RTC Real TimeClock/Calendar/
CPU Supervisor with EEPROM
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
• CPU Supervisor Functions
— Power-On Reset, Low Voltage Sense
— Watchdog Timer (SW Selectable: 0.25s, 0.75s,
1.75s, off)
• 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 I
2
C*
— 400kHz Data Transfer Rate
• Low Power CMOS
— 1.25µA Operating Current (Typical)
• Small Package Options
— 8 Ld SOIC and 8 Ld TSSOP
• Repetitive Alarms
• Temperature Compensation
• Pb-Free Plus Anneal Available (RoHS Compliant)
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
DESCRIPTION
The X1227 device is a Real Time Clock with
clock/calendar, two polled alarms with integrated 512x8
EEPROM, oscillator compensation, CPU Supervisor
(POR/LVS and WDT) 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.
BLOCK DIAGRAM
X1
X2
Oscillator
Frequency
Timer
Logic
Divider
Calendar
8
Control/
Registers
1Hz
Time
Keeping
Registers
Alarm Regs
Compare
Mask
RESET
Control
Decode
Logic
Alarm
(EEPROM)
(EEPROM)
SCL
SDA
Serial
Interface
Decoder
4K
EEPROM
ARRAY
Watchdog
Timer
Low Voltage
Reset
Registers
Status
(SRAM)
V
CC
V
BACK
32.768kHz
(SRAM)
Battery
Circuitry
Switch
OSC
Compensation
Data Sheet May 8, 2006
N
O
T
R
E
C
O
M
M
E
N
D
E
D
F
O
R
N
E
W
D
E
S
I
G
N
S
S
E
E
I
S
L
1
2
0
2
7
