Key Features

• Integrated NV SRAM, RTC, Crystal, Power-Fail Control Circuit, and Lithium Energy Source
• Clock Registers are Accessed Identically to the Static RAM; These Registers are Resident in the 16 Top RAM Locations
• 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 Leap Year 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

DS1553, DS1553P: Block Diagram