Maxim
/
Products
/
Analog
/
Real-Time Clock IC - RTC
/
DS1244
Analog Real-Time Clock IC - RTC DS1244
Top

DS1244

Download

256k NV SRAM with Phantom Clock

Printable Data Sheet Subscribe

Product Details

See parametric specs for Timekeeping & Real-Time Clocks

Key Features

See parametric specs for Timekeeping & Real-Time Clocks
Parametric specs for Timekeeping & Real-Time Clocks
Interface Bytewide
Phantom Clock
VSUPPLY (V) 5
Date/ Time Format (hh = sec/100) YY-MM-DD/ HH:MM:SS:hh
Memory Type NV SRAM
Memory Size (Bytes) 32K
Time of Day Alarms 0
Package/Pins MOD/28
PWRCP/34
Budgetary
Price (See Notes) 		20.54
See parametric specs for Timekeeping & Real-Time Clocks
View Less

Simplified Block Diagram

Technical Docs

Data Sheet 256k NV SRAM with Phantom Clock Dec 14, 2011
App Note Using the SmartWatch/Phantom Clocks with a Microcontroller
App Note PowerCap Package Allows for Density Upgrades, Surface Mount Assembly
App Note Design Considerations for Maxim Real-Time Clocks
App Note Dallas Real Time Chip (RTC) Guide | Maxim Integrated
App Note How to Replace a DS1216 SmartSocket with an Equivalent-Density Phantom Clock Module
App Note Lithium Battery Content in Maxim Products
Tutorial State Machine Logic in Binary-Coded Decimal (BCD)-Formatted Real-Time Clocks
Tutorial Tips for Writing Bulletproof Real-Time Clock Control Code

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .

Sampling:
Selecting the Sample button above will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.

Parameters

Parametric specs for Timekeeping & Real-Time Clocks
Interface Bytewide
Phantom Clock
VSUPPLY (V) 5
Date/ Time Format (hh = sec/100) YY-MM-DD/ HH:MM:SS:hh
Memory Type NV SRAM
Memory Size (Bytes) 32K
Time of Day Alarms 0
Package/Pins MOD/28
PWRCP/34
Budgetary
Price (See Notes) 		20.54
See parametric specs for Timekeeping & Real-Time Clocks

Key Features

  • Real-Time Clock (RTC) Keeps Track of Hundredths of Seconds, Minutes, Hours, Days, Date of the Month, Months, and Years
  • 32k 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
  • Full 10% Operating Range
  • Over 10 Years of Data Retention in the Absence of Power
  • Lithium Energy Source is Electrically Disconnected to Retain Freshness Until Power is Applied for the First Time
  • DIP Module Only
  • Standard 28-Pin JEDEC Pinout
  • PowerCap Module Board Only
    • Surface mountable package for direct connection to PowerCap containing battery and crystal
    • Replaceable battery (PowerCap)
    • Pin-for-pin compatible with DS1248P and DS1251P
  • Available in Lead-Free Package

Applications/Uses

Description

The DS1244 256k NV SRAM with a Phantom clock is a fully static nonvolatile RAM (NV SRAM) (organized as 32k words by 8 bits) with a built-in real-time clock. The DS1244 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 for hundredths of seconds, seconds, minutes, hours, days, date, months, and years. The date at the end of the month is automatically adjusted for months with fewer 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.

Simplified Block Diagram

DS1244, DS1244P: Typical Operating Circuit DS1244, DS1244P: Typical Operating Circuit Zoom icon

Technical Docs

Data Sheet 256k NV SRAM with Phantom Clock Dec 14, 2011
App Note Using the SmartWatch/Phantom Clocks with a Microcontroller
App Note PowerCap Package Allows for Density Upgrades, Surface Mount Assembly
App Note Design Considerations for Maxim Real-Time Clocks
App Note Dallas Real Time Chip (RTC) Guide | Maxim Integrated
App Note How to Replace a DS1216 SmartSocket with an Equivalent-Density Phantom Clock Module
App Note Lithium Battery Content in Maxim Products
Tutorial State Machine Logic in Binary-Coded Decimal (BCD)-Formatted Real-Time Clocks
Tutorial Tips for Writing Bulletproof Real-Time Clock Control Code

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .

Sampling:
Selecting the Sample button above will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.