DS1554P-70+

Real Time Clock Overview

The DS1554P-70+ is a nonvolatile timekeeping RAM device integrating a real-time clock (RTC), 32k x 8 static RAM, crystal oscillator, and lithium energy source. It operates at 5.0V with a typical active supply current of 75mA. The RTC provides BCD-coded timekeeping up to the year 2100 with automatic leap-year compensation. Data retention exceeds 10 years in battery backup mode. The device features power-fail write protection, programmable watchdog timer, and alarm functions. It utilizes a parallel interface with 15 address lines and 8 data lines.

Real Time Clock Feature Summary

• Integrated 32k x 8 NV SRAM with Y2K-compliant RTC
• Built-in lithium battery source for >10 years data retention
• Programmable watchdog timer and RTC alarm with interrupt output
• Power-fail detection with automatic write protection

Real Time Clock Applications

• Industrial control systems requiring precise timekeeping
• Data logging equipment needing nonvolatile storage
• Telecommunications infrastructure timing modules
• Embedded systems with strict power-fail safety requirements

Real Time Clock Procurement Notes

Verify package compatibility as the PowerCap module requires a separate DS9034PCX component containing the crystal and battery. Confirm temperature grade; the P-70 suffix indicates commercial range (0°C to +70°C). Ensure ordering documentation specifies lead-free status indicated by the '+' suffix. Check for specific revision errata if critical timing margins are required.

Real Time Clock Selection Notes

Select this part for applications requiring integrated RTC and large NVSRAM without external components. Compare with DS1554W variants if 3.3V operation is needed. Verify that the 34-pin PowerCap form factor fits the mechanical constraints. Consider the DS1554P-70IND+ variant if industrial temperature range (-40°C to +85°C) is required.

Real Time Clock Part Context

This component belongs to the Maxim Integrated DS1554 family of timekeeping RAMs. It is functionally similar to the DS1553 but offers larger memory capacity. The 'P' designation denotes the 34-pin PowerCap module package, distinct from the 32-pin EDIP DIP package. It serves as a drop-in replacement for older Dallas Semiconductor RTC/NVRAM solutions.

Real Time Clock Replacement Considerations

Direct substitutes include other DS1554 variants with different voltage or temperature ratings. For 3.3V operation, consider the DS1554WP-120+. For industrial temperature, use DS1554P-70IND+. Ensure the replacement supports the same 34-pin PowerCap interface and pinout compatibility.