DS1553P-70

Real Time Clock Overview

The DS1553P-70 is a Year-2000-compliant real-time clock/calendar with 64kB nonvolatile static RAM. It integrates the RTC, crystal, lithium energy source, and power-fail control circuit in a 34-pin PowerCap module. The device uses a byte-wide parallel interface where RTC registers reside in the top 16 locations of the SRAM. It supports BCD-coded timekeeping up to the year 2100 with automatic leap year compensation. Key features include a programmable watchdog timer, RTC alarm, battery voltage monitoring, and precision power-on reset.

Real Time Clock Feature Summary

• Integrated NV SRAM (64kB), RTC, crystal, and lithium battery backup
• Byte-wide parallel interface with double-buffered RTC registers
• Programmable watchdog timer and RTC alarm with interrupt output
• Power-fail write protection and precision power-on reset

Real Time Clock Applications

• Industrial systems requiring precise timekeeping and data retention
• Embedded controllers needing nonvolatile memory and system reset management
• Equipment requiring Y2K compliance and long-term battery-backed operation

Real Time Clock Procurement Notes

Verify component authenticity through authorized distributors or manufacturer channels. Confirm package integrity for the 34-pin PowerCap module. Check for lead-free/RoHS compliance markings on the top mark. Ensure the separate DS9034PCX PowerCap accessory is ordered if not included. Validate that the specific revision matches design requirements regarding access times.

Real Time Clock Selection Notes

Select the DS1553P-70 for applications requiring integrated timekeeping and substantial nonvolatile storage. The PowerCap package allows surface-mount assembly before attaching the battery module. Ensure the system VCC supply aligns with the 5V or 3.3V operating range. Verify that the parallel interface timing constraints meet the microcontroller's capabilities. Consider the 10-year data retention specification for long-life deployments.

Real Time Clock Part Context

The DS1553 belongs to the Maxim Integrated DS1553 family of real-time clocks. It is available in 28-pin EDIP and 34-pin PowerCap packages. The P suffix denotes the PowerCap module variant. Other variants include DS1553-85+ and DS1553W-120+. The device is designed for high-reliability applications requiring combined RTC and NVSRAM functionality.

Real Time Clock Replacement Considerations

Public confirmed substitute part numbers are not provided in the verified documentation. Consult Analog Devices/Maxim Integrated for current equivalent products or updated series replacements.