DS1744P-70IND

Real Time Clock Overview

The DS1744P-70IND is a Y2K-compliant, nonvolatile timekeeping RAM integrating a real-time clock/calendar and 32k x 8 static RAM. It operates on a single 5V supply within an industrial temperature range of -40°C to +85°C. The device utilizes a standard JEDEC byte-wide parallel interface, with RTC registers mapped to the eight top RAM locations (7FF8h–7FFFh). Key features include automatic leap-year compensation valid until 2100, power-fail write protection, and a lithium energy source providing over 10 years of data retention without VCC. The component is housed in a 34-pin PowerCap module package.

Real Time Clock Feature Summary

• Integrated NV SRAM, RTC, crystal, power-fail control circuit, and lithium battery
• Y2K compliant with century register and automatic leap-year correction through 2100
• Standard JEDEC 32k x 8 static RAM pinout with identical access to clock registers
• Power-fail write protection ensures data integrity during voltage out-of-tolerance conditions

Real Time Clock Applications

• Industrial systems requiring precise timekeeping and nonvolatile data storage
• Embedded controllers needing Y2K-compliant calendar functions
• Equipment requiring extended battery-backed memory retention

Real Time Clock Procurement Notes

Verify that the specific application requires the 34-pin PowerCap module format rather than the 28-pin EDIP variant. Confirm compatibility with the separate DS9034PCX+ or DS9034I-PCX+ PowerCap unit, which must be ordered separately to provide the necessary crystal and battery components for this package type.

Real Time Clock Selection Notes

Select the DS1744P-70IND when surface-mount assembly is required prior to attaching the battery module, as this prevents thermal damage to the internal crystal and lithium source. Ensure the design supports the 34-pin footprint and accounts for the separate ordering of the PowerCap accessory. Verify that the system logic can handle the double-buffered register updates to prevent reading incorrect time data.

Real Time Clock Part Context

This part belongs to the DS174xP family of nonvolatile timekeeping RAMs. It shares functional similarities with the DS1744 series but differs in packaging. While the DS1744 uses a 28-pin encapsulated DIP, the DS1744P utilizes a 34-pin PowerCap module board designed for surface mounting before the addition of the external PowerCap unit containing the energy source.

Real Time Clock Replacement Considerations

Direct substitutes include other densities within the DS174xP family, such as the DS1746P or DS1747P, provided the memory capacity meets system requirements. These parts maintain pin-for-pin compatibility with the DS1744P.