DS14285SN+

Real Time Clock Overview

The DS14285SN+ is a real-time clock (RTC) and calendar integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It operates within a supply voltage range of 4.5V to 5.5V and supports an industrial temperature range of -40°C to +85°C. The device features a multiplexed bus interface, providing 114 bytes of general-purpose nonvolatile RAM alongside 14 bytes of clock and control registers. It counts seconds, minutes, hours, days, dates, months, and years with leap year compensation valid up to the year 2100. The component is housed in a 24-pin SOIC package.

Real Time Clock Feature Summary

• Direct replacement for IBM AT computer clock/calendar functions
• Functionally compatible with DS1285/DS1287 standards
• Automatic backup supply and write protection for external SRAM
• Multiplexed bus interface for pin efficiency

Real Time Clock Applications

• IBM AT computer systems
• Industrial embedded controllers requiring RTC functionality
• Systems utilizing external SRAM for nonvolatile data retention

Real Time Clock Procurement Notes

Verify the specific suffix 'SN+' indicates the industrial temperature grade (-40°C to +85°C) and lead-free/RoHS compliance as defined in the ordering information table. Confirm the 24-SOIC package dimensions match the design footprint. Check current manufacturing status as some variants in this family may be discontinued.

Real Time Clock Selection Notes

Select the DS14285SN+ when an industrial temperature range is required compared to the commercial DS14285S+. Ensure the system design accommodates the multiplexed bus timing (Intel mode default) or utilizes the MOT pin if using the PLCC variant. Verify that the external crystal load capacitance matches the internal oscillator requirements of 6 pF.

Real Time Clock Part Context

This component belongs to the DS14285/DS14287 family of real-time clocks with NVRAM control. It serves as a successor to industry-standard DS12885 and DS12887 devices. The SN+ designation specifically denotes the surface-mount SOIC package variant with extended industrial temperature capabilities and lead-free construction.

Real Time Clock Replacement Considerations

Public confirmed substitute part numbers: None listed in verified documentation.