DS12887

Real Time Clock Overview

The DS12887+ is a real-time clock (RTC) and calendar integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It provides timekeeping for seconds, minutes, hours, date, day of the week, month, and year with leap year compensation through 2099. The device features 114 bytes of battery-backed static RAM and supports both 12-hour and 24-hour time formats. It operates on a single 5V supply (4.5V to 5.5V) with an integrated lithium battery backup (2.5V to 4V). The component utilizes a multiplexed parallel bus interface and is housed in a 24-pin EDIP module package designed for through-hole mounting.

Real Time Clock Feature Summary

• Integrated quartz crystal and lithium energy source within a 24-pin encapsulated DIP package
• 114 bytes of battery-backed static RAM for general-purpose data storage
• Automatic date adjustment for months with fewer than 31 days and leap year correction
• Programmable square wave output and one time-of-day alarm with three maskable interrupts

Real Time Clock Applications

• Embedded systems requiring precise timekeeping
• Utility meters and smart grid infrastructure
• Network hubs, bridges, and routers

Real Time Clock Procurement Notes

Verify the specific suffix designation when ordering, as it may indicate temperature range or packaging variations. Confirm RoHS compliance status with the manufacturer or distributor prior to procurement. Check current availability as supply constraints may affect lead times. Ensure the selected package variant matches the PCB footprint requirements for the 24-EDIP module form factor.

Real Time Clock Selection Notes

Select the DS12887+ when an integrated crystal and battery solution is required to minimize board space. This part is suitable for designs needing 114 bytes of non-volatile memory alongside RTC functions. Compare against the DS12C887 if a century byte at address 32h is necessary, noting the DS12887 lacks this specific feature. Ensure the system voltage aligns with the 4.5V to 5.5V operating range.

Real Time Clock Part Context

The DS12887+ belongs to the DS12887 series of real-time clocks. It serves as a direct replacement for older components like the DS1285 and DS1287. The device shares functional similarities with the DS12C887, though the latter includes a century byte. It is part of the broader Maxim Integrated portfolio of clock and timer ICs designed for industrial and commercial applications.

Real Time Clock Replacement Considerations

The DS12887+ is documented as a direct replacement for the DS1285 and DS1287. Designers should verify pin compatibility and software register mappings when migrating from these legacy parts.