DS1284Q+T&R

Overview

The DS1284Q+T&R is a real-time clock (RTC) integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It provides clock/calendar functionality with a parallel interface and includes 50 bytes of static RAM. The device supports 12/24-hour time formats and YY-MM-DD-dd date formats. Key features include an alarm, leap year compensation, square wave output, SRAM, and a watchdog timer. It operates on a 4.5V to 5.5V supply voltage with a battery backup range of 2.4V to 3.5V. Maximum timekeeping current is 7mA at 5V. The component is housed in a 28-PLCC package and is rated for an operating temperature range of 0°C to 70°C.

Feature Summary

• Integrated 50-byte static RAM for data storage
• Hardware watchdog timer for system reliability
• Automatic leap year correction up to 2099
• Programmable square wave output

Applications

• Industrial control systems requiring precise timekeeping
• Data logging equipment with parallel bus interfaces
• Embedded systems needing battery-backed memory and RTC functions

Procurement Notes

Verify the specific suffix +T&R indicates tape and reel packaging when sourcing. Confirm the 28-PLCC footprint compatibility with the target PCB design. Ensure the parallel interface requirements match the host microcontroller or processor capabilities. Check for RoHS compliance documentation if required by project specifications.

Selection Notes

Select this component when a parallel interface is preferred over serial alternatives like I2C or SPI. The 50-byte SRAM capacity suits applications requiring moderate non-volatile data retention alongside timekeeping. Consider the 0°C to 70°C industrial temperature range against environmental conditions. Evaluate the 7mA maximum current consumption against power budget constraints.

Part Context

This part belongs to the DS1284 series of real-time clocks from Maxim Integrated. It serves as a direct replacement for legacy RTC designs using parallel interfaces. The device integrates timing, calendar, and memory functions into a single package, simplifying board layout compared to discrete solutions.

Replacement Considerations

Check pin-to-pin compatibility with existing DS1284 variants. Verify that the parallel interface timing parameters meet the host system's requirements. Ensure the 28-PLCC package dimensions fit the available space.