Features and Benefits
- Compatible with Crystal ESR Up to 100kΩ Allows a Crystal to be Optimized for Cost and Space
- Low-Power Operation Extends Battery Backup Run Time
- Low Timekeeping Current of 250nA (typ)
- Automatic Power-Fail Detect and Switch Circuitry
- Completely Manages All Timekeeping Functions
- Real-Time Clock Counts Seconds, Minutes, Hours, Date of the Month, Month, Day of the Week, and Year with Leap-Year Compensation Valid Up to 2400
- External Clock Source for Synchronization Clock Reference (e.g., 32kHz, 50Hz/60Hz Powerline, GPS 1PPS)
- 56-Byte, Battery-Backed, General-Purpose RAM with Unlimited Writes
- Programmable Square-Wave Output Signal
- Simple Serial Port Interfaces with Most Microcontrollers
- I2C Serial Interface
- Industrial Temperature Range: -40°C to +85°C Supports Operation in a Wide Range of Applications
- Underwriters Laboratories (UL®) Recognized
The DS1308 serial real-time clock (RTC) is a low-power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV RAM. Address and data are transferred serially through an I²C interface. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with an AM/PM indicator. The DS1308 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time and date operation.
- Consumer Electronics (Set-Top Box, Digital Recording, Network Appliance)
- Handhelds (GPS, POS Terminal)
- Medical (Glucometer, Medicine Dispenser)
- Office Equipment (Fax/Printer, Copier)
- Other (Utility Meter, Vending Machine, Thermostat, Modem)
- Telecommunications (Router, Switcher, Server)
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Documentation & Resources
DS1308 Reliability Data1/12/2023
Oscillator Design Considerations for Low-Current Applications1/26/2011
Selecting a Backup Source for Real-Time Clocks5/26/2006
Using the DS32kHz with Maxim Real-Time Clocks2/15/2002
Design Considerations for Maxim Real-Time Clocks2/15/2002
Crystal Considerations with Maxim Real-Time Clocks (RTCs)3/29/2001
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
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Buy Now Pricing
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