DS1306+

Real Time Clock Overview

The DS1306+ is a serial alarm real-time clock (RTC) manufactured by Analog Devices Inc./Maxim Integrated, housed in a 16-pin DIP package. It provides binary coded decimal (BCD) timekeeping for seconds, minutes, hours, date, month, and year with leap-year compensation valid through 2100. The device includes 96 bytes of battery-backed NV RAM and two programmable time-of-day alarms. It operates on a single supply voltage ranging from 2.0V to 5.5V and supports both SPI (Modes 1 and 3) and standard 3-wire serial interfaces. The component ensures continuous operation via dual power supply pins for primary and backup sources.

Real Time Clock Feature Summary

• Integrated BCD calendar and clock with automatic end-of-month adjustments and leap-year compensation valid up to the year 2100.
• Dual-power architecture supporting primary supply (VCC1), secondary supply (VCC2), and battery input (VBAT) with optional trickle charging.
• Flexible serial interface compatibility with Motorola SPI Modes 1 and 3 or standard 3-wire communication via the SERMODE pin.
• Two independent time-of-day alarms with programmable interrupt outputs (INT0 and INT1) based on specific time matches.

Real Time Clock Applications

• Systems requiring precise timekeeping with low-power battery backup capabilities.
• Data logging devices needing non-volatile storage for timestamps.
• Industrial control systems utilizing SPI or 3-wire microcontroller interfaces.
• Portable electronics operating within a 2.0V to 5.5V voltage range.

Real Time Clock Procurement Notes

Verify the specific suffix requirements for lead-free compliance and temperature range before ordering. The '+' suffix indicates a lead-free/RoHS-compliant package. Confirm that the 16-pin DIP form factor aligns with the target PCB layout. Ensure the selected variant meets the commercial (0°C to +70°C) or industrial (-40°C to +85°C) temperature specifications required for the application environment.

Real Time Clock Selection Notes

Select the DS1306+ when a 16-pin DIP package is necessary for through-hole mounting. Choose this model over the TSSOP variants if space constraints are less critical than ease of prototyping or manual assembly. Verify that the system logic levels are compatible with the VCCIF pin if interfacing with 3V logic in mixed-supply environments. Ensure the microcontroller supports either SPI or 3-wire protocols as dictated by the SERMODE pin configuration.

Real Time Clock Part Context

The DS1306+ belongs to the DS1306 family of serial alarm real-time clocks. It shares core functionality with other variants such as the DS1306N+ and DS1306EN+, differing primarily in packaging and temperature ratings. The '+' designation specifically denotes a lead-free and RoHS-compliant manufacturing process compared to older non-suffixed versions. This component serves as a dedicated timing solution for embedded systems requiring reliable calendar and alarm functions.

Real Time Clock Replacement Considerations

Direct replacements include other members of the DS1306 family, such as the DS1306N+ for identical electrical performance in a DIP-16 package. For surface-mount applications, the DS1306E+ (20-TSSOP) offers equivalent functionality with a different footprint. Verify that any substitute maintains the same serial interface protocol and voltage operating range of 2.0V to 5.5V.