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 or +5V 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 NV 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
Battery Voltage-Level Indicator Flags
Available as Chip (DS1501) or Stand-Alone
Module with Embedded Battery and Crystal
(DS1511)
UL Recognized
ApplicationRemote Systems
Battery-Backed Systems
Telecom Switches
Office Equipment
Consumer Electronics
Pinout
SpecificationsVoltage Range on Any Pin Relative to Ground....................................-0.5V to +6.0V
Operating Temperature Range (Module).......................................0.5to +70
Operating Temperature Range, DS1501......................................-40 to +85 (Note 1)
Operating Temperature Range, DS1511.......................................0 to +70
Storage Temperature Range, DS1501..................................................-55 to +125
Storage Temperature Range, DS1511........................................-40 to +70
Soldering Temperature (DIP, Module)..........+260 Lead Temperature for 10 seconds (max) (Note 2)
Soldering Temperature (SO, TSOP).......................ee IPC/JEDEC J-STD-020A for Surface-Mount Devices
DescriptionThe 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.
DS1501 Data Sheet
