DS1251:4096K NV SRAM with Phantom Clock

The DS1251 4096K NV SRAM with Phantom Clock is a fully static nonvolatile RAM (organized as 512K words by 8 bits) with a built-in real-time clock. The DS1251Y has a self-contained lithium energy source and control circuitry which constantly monitors VCC for an out-of-tolerance condition. When such a condition occurs, the lithium energy source is automatically switched on and write protection is unconditionally enabled to prevent garbled data in both the memory and real-time clock. The Phantom Clock provides timekeeping information including hundredths of seconds, seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with less than 31 days, including correction for leap years. The Phantom Clock operates in either 24-hour or 12-hour format with an AM/PM indicator.

Key Features
  • Real-Time Clock Keeps Track of Hundredths Of Seconds, Minutes, Hours, Days, Date of the Month, Months, and Years
  • 512k x 8 NV SRAM Directly Replaces Volatile Static RAM or EEPROM
  • Embedded Lithium Energy Cell Maintains Calendar Operation and Retains RAM data
  • Watch function is Transparent to RAM Operation
  • Automatic Leap Year Compensation Valid Up to 2100
  • Over 10 Years of Data Retention in the Absence of Power
  • Full 10% Operating Range
  • Lithium Energy Source is Electrically Disconnected to Retain Freshness until Power is Applied for the First Time
  • DIP Module Only
    • Standard 32-Pin JEDEC Pinout
    • Upward Compatible with the DS1248
  • PowerCap Module Board Only
    • Surface Mountable Package for Direct Connection to PowerCap Containing Battery and Crystal
    • Replaceable Battery (PowerCap)
    • Pin-for-Pin Compatible with Other Densities of DS124xP Phantom Clocks
DS1251, DS1251P: Pin Configuration
DS1251, DS1251P: Pin Configuration
DataSheet
titleDownload file
DS1251-DS1251P Data SheetDS1251-DS1251P.pdf
Parametrics
Part NumberInterfaceVSUPPLY
(V)
Memory TypeMemory Size
(Bytes)
Time of Day AlarmsFunctionsPackage/PinsBudgetary
Price
See Notes
DS1251Bytewide
Phantom Clock
3.3
5
NV SRAM512K0RTCEDIP/32
PCAP/34
$22.19 @1k
Quality and Environmental Data
Related Products
Ordering Information
Part NumberNotesStatusRecommended ReplacementPackageTempRoHS
DS1251W-120+ActiveEDIP,;32 pin;707.2 mm²0°C to +70°CLead Free
DS1251W-120IND+ActiveEDIP,;32 pin;707.2 mm²-40°C to +85°CLead Free
DS1251WP-1203.3V, 120nsNo Longer AvailableDS1251WP-120+PCAP,;34 pin;596.9 mm²0°C to +70°CSee data sheet
DS1251WP-120+ActivePCAP,;34 pin;596.9 mm²0°C to +70°CLead Free
DS1251WP-120IND+ActivePCAP,;34 pin;596.9 mm²-40°C to +85°CLead Free
DS1251Y-705V, 70nsNo Longer AvailableDS1251Y-70+EDIP,;32 pin;707.2 mm²0°C to +70°CSee data sheet
DS1251Y-70+ActiveEDIP,;32 pin;707.2 mm²0°C to +70°CLead Free
DS1251YP-70No Longer AvailableDS1251YP-70+PCAP,;34 pin;596.9 mm²0°C to +70°CSee data sheet
DS1251YP-70+ActivePCAP,;34 pin;596.9 mm²0°C to +70°CLead Free
DS1251YP-70INDNo Longer AvailableDS1251YP-70IND+PCAP,;34 pin;596.9 mm²-40°C to +85°CSee data sheet
Part NumberNotesStatusRecommended ReplacementPackageTempRoHS
DS1251YP-70IND+ActivePCAP,;34 pin;596.9 mm²-40°C to +85°CLead Free
DS1251-DS1251P.pdf DS1251
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DS1251.pdf DS1251
DS1251-DS1251P.pdf DS1251