GENERAL DESCRIPTION
The DS1501/DS1511 are full-function, year 2000-compliant real-time clock/calendars (RTCs) with an RTC alarm, watchdog timer, power-on reset, battery monitors, 256 bytes NV SRAM, and a 32.768kHz output. User access to all registers within the DS1501/DS1511 is accomplished with a byte-wide interface, as shown in Figure 8. The RTC registers contain century, year, month, date, day, hours, minutes, and seconds data in 24-hour binary-coded
decimal (BCD) format. Corrections for day of month and leap year are made automatically.

FEATURES
BCD-Coded Century, Year, Month, Date, Day, Hours, Minutes, and Seconds with Automatic Leap-Year Compensation Valid Up to the Year 2100
Programmable Watchdog Timer and RTC Alarm
Century Register; Y2K-Compliant RTC
+3.3 (W) or +5V (Y) Operation
Precision Power-On Reset
Power-Control Circuitry Support System
  Power-On from Date/Day/Time Alarm or Key
  Closure/Modem-Detect Signal
256 Bytes Battery-Backed SRAM
Auxiliary Battery Input
Accuracy of DS1511 Better than ±1 Minute/Month at +25°C
Day-of-Week/Date Alarm Register
Crystal Select Bit Allow RTC to Operate with 6pF or 12.6pF Crystal (DS1501)
Battery Voltage-Level Indicator Flags
Available as Chip (DS1501) or Stand-Alone
  Encapsulated DIP Module with Embedded
  Battery and Crystal (DS1511)

APPLICATIONS
Remote Systems
Battery-Backed Systems
Telecom Switches
Office Equipment
Consumer Electronics
Underwriters Laboratories (UL) Recognized