DS1553-100

Real Time Clock Overview

The DS1553-100 is a Year-2000-compliant real-time clock/calendar integrated with 64kB nonvolatile static RAM. It operates at 5.0V within a commercial temperature range of 0°C to +70°C and utilizes a parallel byte-wide interface. The device features double-buffered RTC registers, an alarm function, watchdog timer, power-on reset, and battery monitoring. Data retention exceeds 10 years via an internal lithium source that disconnects until initial power application.

Real Time Clock Feature Summary

• Integrated 64kB NV SRAM with RTC registers mapped to the top 16 memory locations
• Year-2000 compliant with automatic leap year compensation valid through 2100
• Includes programmable watchdog timer, RTC alarm, and precision power-on reset
• Battery voltage level indicator flag and power-fail write protection

Real Time Clock Applications

• Industrial systems requiring long-term timekeeping without external components
• Embedded controllers needing combined timekeeping and persistent data storage
• Equipment requiring Y2K compliance and automatic calendar corrections

Real Time Clock Procurement Notes

Verify package type availability as the DS1553-100 corresponds to the 28-pin EDIP module. Confirm lead-free status (+ suffix) if required by assembly specifications. Check for current production status as older revisions may be discontinued or subject to supply constraints.

Real Time Clock Selection Notes

Select the DS1553-100 for 5V parallel interface designs requiring integrated timekeeping and substantial nonvolatile storage. Ensure system design accommodates the 28-pin EDIP footprint. Verify compatibility with the specific access times (85ns/100ns) relative to the host microcontroller bus speed.

Real Time Clock Part Context

The DS1553 series consolidates RTC, SRAM, crystal, and lithium battery into a single encapsulated module. The -100 suffix denotes the 5.0V operating variant in the 28-pin EDIP package. This integration simplifies PCB layout by eliminating discrete backup power and timing components.

Real Time Clock Replacement Considerations

Direct replacements are limited due to the integrated nature of the component. Consider the DS1553P-100+ for surface-mount applications using the PowerCap module, though it requires separate ordering of the DS9034PCX accessory.