DS1308
PRODUCTIONLow-Current I²C RTC with 56-Byte NV RAM
Compatible with Any 32.768kHz Crystal
- Part Models
- 6
- 1ku List Price
- Starting From $2.04
Overview
- 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.
Applications
- 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)
Documentation
Data Sheet 1
Reliability Data 1
Design Note 5
Technical Articles 2
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. View our quality and reliability program and certifications for more information.
| Part Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| DS1308U-18+ | Micro-MAX, Thin Shrink Small-Outline | ||
| DS1308U-18+T | Micro-MAX, Thin Shrink Small-Outline | ||
| DS1308U-3+ | Micro-MAX, Thin Shrink Small-Outline | ||
| DS1308U-3+T | Micro-MAX, Thin Shrink Small-Outline | ||
| DS1308U-33+ | Micro-MAX, Thin Shrink Small-Outline | ||
| DS1308U-33+T | Micro-MAX, Thin Shrink Small-Outline |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
Sep 19, 2018 - 1753N ASSEMBLY |
||
| DS1308U-18+ | PRODUCTION | |
| DS1308U-18+T | PRODUCTION | |
| DS1308U-3+ | PRODUCTION | |
| DS1308U-3+T | PRODUCTION | |
| DS1308U-33+ | PRODUCTION | |
| DS1308U-33+T | PRODUCTION | |
This is the most up-to-date revision of the Data Sheet.