DS12885S/T&R

Overview

The DS12885S+T&R is a real-time clock and calendar integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It provides timekeeping in either 12-hour or 24-hour format with an AM/PM indicator, alongside date tracking including leap year correction. The device features 114 bytes of battery-backed static RAM (NVSRAM) for data storage. It operates on a primary supply voltage ranging from 4.5 V to 5.5 V, with a backup battery range of 2.5 V to 4 V. The maximum current consumption during timekeeping is 15 mA at the nominal supply voltage. The component is housed in a 24-SOIC surface-mount package.

Feature Summary

• Integrated real-time clock/calendar with automatic month-end adjustments and leap year correction.
• Includes 114 bytes of non-volatile static RAM (NVSRAM) for user data storage.
• Supports multiplexed parallel interface for system connectivity.
• Features programmable square wave output, one time-of-day alarm, and three maskable interrupts.

Applications

• Industrial control systems requiring precise time synchronization.
• Data logging equipment needing persistent timestamping.
• Telecommunications infrastructure maintaining network time standards.
• Embedded computing platforms utilizing parallel bus architectures.

Procurement Notes

Verify the specific suffix 'T&R' indicates Tape & Reel packaging when sourcing components. Confirm RoHS compliance status through official manufacturer documentation prior to integration. Ensure the selected variant matches the required operating temperature range of 0°C to +70°C for the intended application environment.

Selection Notes

Select this component for designs requiring a direct replacement for legacy DS1285/DS1287 devices using a parallel interface. Consider the 15 mA maximum current draw against available power budgets. Verify that the 24-SOIC footprint aligns with the PCB layout constraints and that the 4.5 V to 5.5 V supply rail is stable within the specified limits.

Part Context

The DS12885 series serves as a successor to earlier Maxim RTC models like the DS1285 and DS1287. It integrates quartz crystal and lithium energy source capabilities in specific package variants, though the S version utilizes external components. The family supports both standard and industrial temperature grades, providing flexibility for various commercial and industrial deployment scenarios.

Replacement Considerations

The DS12885S is designed as a direct pin-compatible replacement for the DS1285 and DS1287. When substituting older parts, verify that the interrupt logic levels and address decoding schemes remain compatible with the host microcontroller's parallel bus interface.