DS1284Q/T&R

Overview

The DS1284Q/T&R is a real-time clock and calendar IC manufactured by Analog Devices Inc./Maxim Integrated. It features a parallel interface and is housed in a 28-PLCC package with J-leads. The device operates on a 4.5V to 5.5V supply, consuming up to 7mA at 5V during timekeeping. It includes 50 bytes of SRAM and supports 12/24-hour time formats with HH:MM:SS:hh precision. Date formatting follows YY-MM-DD-dd. Key features include an alarm, leap year compensation, square wave output, and a watchdog timer. It functions within a 0°C to 70°C temperature range.

Feature Summary

• Integrated 50-byte battery-backed SRAM for data storage
• Hardware watchdog timer for system reliability
• Automatic leap year correction and date adjustment
• Programmable square wave output and one-time-of-day alarm

Applications

• Industrial control systems requiring precise timekeeping
• Data logging equipment needing non-volatile memory backup
• Embedded systems with parallel bus interfaces

Procurement Notes

Verify the specific ordering suffix matches the required tape and reel packaging configuration. Confirm that the 28-PLCC footprint aligns with the target PCB design. Ensure voltage levels are compatible with the 4.5V to 5.5V operating range. Check for any lead-free or environmental compliance requirements if applicable to the end product specifications.

Selection Notes

Select this component when a parallel interface is preferred over serial alternatives like I2C. The 50-byte SRAM capacity suits applications with moderate data storage needs. Consider the 7mA current consumption against power budget constraints. The watchdog timer feature is critical for systems requiring fault detection without external components.

Part Context

This part belongs to the DS1284 series of real-time clocks. It serves as a direct replacement for older discrete RTC solutions. The T&R suffix indicates it is supplied in a tape and reel format for automated assembly processes. It shares functional similarities with other Maxim Integrated RTCs but differs in interface type and memory size.

Replacement Considerations

Direct pin-compatible replacements may exist within the same family, such as the DS1284Q. Verify electrical parameters and feature sets before substitution. Serial RTCs like the DS1338 require interface adaptation.