DS1556W-120IND+

The DS1556 is a full-function, year-2000-compliant (Y2KC), real-time clock/calendar (RTC) with an RTC alarm, watchdog timer, power-on reset, battery monitor, and 128k x 8 nonvolatile static RAM. User access to all registers within the DS1556 is accomplished with a byte-wide interface as shown in Figure 1.
The RTC registers contain century, year, month, date, day, hours, minutes, and seconds data in 24-hour BCD format. Corrections for day of month and leap year are made automatically.
FEATURES
• Integrated NV SRAM, Real-Time Clock (RTC), Crystal, Power-Fail Control Circuit, and Lithium Energy Source
• Clock Registers are Accessed Identically to the Static RAM;
These Registers Reside in the 16 Top RAM Locations
• Century Byte Register (i.e., Y2K Compliant)
• Totally Nonvolatile with Over 10 Years of Operation in the Absence of Power
• Precision Power-On Reset
• Programmable Watchdog Timer and RTC Alarm
• BCD-Coded Year, Month, Date, Day, Hours, Minutes, and seconds with Automatic LeapYear Compensation Valid Up to the Year 2100
• Battery Voltage-Level Indicator Flag
• Power-Fail Write Protection Allows for 10% VCC Power-Supply Tolerance
• Lithium Energy Source is Electrically Disconnected to Retain Freshness Until Power is Applied for the First Time
• Also Available in Industrial Temperature Range: -40°C to +85°C