DS1251WP-120IND+

Overview

The DS1251WP-120IND+ is a nonvolatile RAM integrated circuit featuring a built-in real-time clock, manufactured by Analog Devices Inc./Maxim Integrated. It provides 512KB of NV SRAM and operates on a parallel interface within a 34-PowerCap™ Module package. The device supports a supply voltage range of 2.97V to 3.63V and maintains data retention for over 10 years using an embedded lithium energy cell. It functions in surface-mount applications across an industrial temperature range of -40°C to +85°C.

Feature Summary

• Integrates 512K x 8 NV SRAM with automatic leap year compensation valid up to 2100
• Includes a phantom clock that tracks hundredths of seconds, minutes, hours, days, dates, months, and years
• Features a replaceable PowerCap module containing the battery and crystal, mounted after soldering
• Supports 12-hour or 24-hour time formats with AM/PM indicators

Applications

• Industrial systems requiring persistent timekeeping and data storage during power loss
• Embedded controllers needing direct replacement for volatile static RAM or EEPROM
• Equipment requiring long-term data retention without external battery maintenance

Procurement Notes

Verify the specific ordering suffix IND+ confirms the -40°C to +85°C industrial temperature rating and 3.3V operation. Confirm that the separate DS9034PCX+ or DS9034I-PCX+ PowerCap modules are included in the assembly plan, as they are not shipped with the IC. Ensure the design accommodates the 34-PowerCap Module footprint and allows space for the top-mounted PowerCap component.

Selection Notes

Select this model when a 512KB capacity is required alongside precise timekeeping. The PowerCap variant is suitable for surface-mount processes where the battery must be added post-reflow to prevent thermal damage. Compare against the DS1251W-120IND+ if a DIP package is preferred, or the DS1248 series if lower memory density suffices. Ensure the system voltage aligns with the 3.3V specification rather than the 5V variants.

Part Context

This component belongs to the DS1251 family of 4096K NV SRAM devices with phantom clocks. The 'WP' designation indicates the PowerCap board-only package, while 'IND+' specifies the industrial temperature grade and lead-free/RoHS compliance. It is upward compatible with the DS1248 series and designed to replace standard volatile memory in systems requiring backup capabilities.

Replacement Considerations

The DS1251WP-120+ serves as the commercial temperature version of this part. For lower density requirements, the DS1248WP-120+ offers 128kB capacity with pin-for-pin compatibility. Verify that any substitute maintains the 34-PowerCap Module form factor and phantom clock communication protocol.