DS12885T/T&R

Overview

The DS12885T/T&R is a real-time clock (RTC) integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It provides clock and calendar functions with a 114-byte non-volatile static RAM (NVSRAM). The device features a parallel interface and operates within a supply voltage range of 4.5V to 5.5V, with battery backup support from 2.5V to 4V. Key specifications include a maximum timekeeping current of 15mA at the nominal supply voltage and an operating temperature range of 0°C to 70°C. It is housed in a 32-TQFP surface-mount package.

Feature Summary

• Integrated 114-byte NVSRAM for data retention during power loss
• Supports Alarm, Daylight Savings Time, Leap Year, and Square Wave Output
• Parallel interface with HH:MM:SS (12/24 hr) time and YY-MM-DD-dd date formats

Applications

• Industrial systems requiring precise timekeeping and data logging
• Embedded controllers needing non-volatile memory backup
• Telecommunications equipment with RTC synchronization needs

Procurement Notes

Verify the Tape & Reel (TR) packaging designation matches the specific reel quantity required for automated assembly processes. Confirm that the 32-TQFP footprint dimensions align with the target PCB layout. Ensure the 4.5V–5.5V VCC requirement is compatible with the system power rail design.

Selection Notes

Select this component when a parallel interface is preferred over serial alternatives like I2C or SPI. The 114-byte NVSRAM capacity should be evaluated against application memory requirements. Consider the 15mA active current consumption relative to system power budgets, as lower-power serial RTCs may be suitable for battery-constrained designs.

Part Context

This part belongs to the DS12885 family of real-time clocks. The 'T' suffix typically denotes the tape and reel packaging variant, while the base model DS12885 offers similar functionality in different packages such as PDIP or SOIC. The series integrates standard RTC capabilities with persistent storage.

Replacement Considerations

Direct replacements include other variants within the DS12885 family, such as the DS12885SN+ or DS12885+, provided the package type (PDIP vs. TQFP) and interface compatibility are verified. Cross-package pinouts may differ.