DS1244W-120

Overview

The DS1244W-120 is a 3.3V Phantom Time Chip featuring 32K x 8 NV SRAM and an integrated real-time clock. It operates within a 2.97V to 3.63V supply range, drawing up to 7mA during timekeeping at 3.3V. The device utilizes a parallel interface with a 120ns access time and supports HH:MM:SS:hh (12/24 hr) time formats alongside YY-MM-DD-dd date formats. Housed in a 28-pin EDIP module for through-hole mounting, it covers a commercial temperature range of 0°C to +70°C.

Feature Summary

• Integrates 32K x 8 Non-Volatile Static RAM with automatic write protection during power failures.
• Includes a phantom clock providing calendar tracking with automatic leap year compensation valid until 2100.
• Features an embedded lithium energy source that maintains data retention for over 10 years without VCC.
• Supports both 12-hour and 24-hour time formats with AM/PM indicators via serial bit stream communication.

Applications

• Industrial control systems requiring persistent timekeeping and volatile memory replacement.
• Embedded devices needing non-volatile storage with built-in calendar functionality.
• Equipment requiring battery-backed RAM to prevent data loss during main power interruptions.

Procurement Notes

Verify the specific suffix indicates the 3.3V operating voltage variant. Confirm the package type matches the required 28-pin EDIP module form factor. Check for lead-free/RoHS compliance status if environmental regulations apply. Ensure the commercial temperature grade (0°C to +70°C) meets system requirements rather than the industrial grade (-40°C to +85°C).

Selection Notes

Select this component when a combined RTC and NVSRAM solution is needed in a DIP module format. Compare against the DS1244Y-70 for 5V applications or the DS1244WP-120 for surface-mount PowerCap configurations. Ensure the host system can support the 64-bit pattern recognition sequence required to access the phantom clock registers.

Part Context

This part belongs to the DS1244 family of Phantom Time Chips manufactured by Analog Devices Inc./Maxim Integrated. It serves as a direct replacement for standard volatile static RAM or EEPROM in systems requiring time-stamped data logging. The W-120 designation specifically identifies the 3.3V version with 120ns access speed in the 28-pin encapsulated DIP package.

Replacement Considerations

The DS1244W-120+ is the lead-free/RoHS-compliant equivalent. For surface-mount needs, consider the DS1244WP-120 paired with a DS9034PCX PowerCap. Industrial temperature variants are available as the DS1244W-120IND+. Verify pin compatibility with existing designs using the standard 28-pin JEDEC layout.