Maxim Integrated DS1244W-120IND Nonvolatile Timekeeping RAM

The DS1244W-120IND is a highly reliable, 4096 x 8 nonvolatile timekeeping RAM product from Maxim Integrated. This device integrates a full-featured real-time clock and calendar, along with a NV SRAM (nonvolatile static random-access memory) that retains data when the primary power supply is turned off. The integrated power-fail deselect circuitry ensures that any write operation in progress will be concluded correctly, which enhances data integrity during power transitions.

Designed for industrial applications, the DS1244W-120IND operates at a voltage range of 4.5V to 5.5V and features an industrial temperature range of -40°C to +85°C, making it suitable for harsh environments. The device's access time of 120ns allows for swift data retrieval and storage, which is crucial for time-sensitive operations in industrial systems.

The real-time clock provides seconds, minutes, hours, day, date, month, and year information, with the added capability of leap year compensation valid up to the year 2100. An integrated lithium energy source ensures up to 10 years of data retention and clock functionality in the absence of external power.

Communication with the DS1244W-120IND is achieved through a simple multiplexed address and data bus interface, which minimizes the number of pins required and simplifies the design process for embedded systems. The device is available in a 28-pin EDIP (Encapsulated Dual In-line Package) or 32-pin TSOP (Thin Small Outline Package), providing flexibility in hardware design.

Key features of the DS1244W-120IND include:

• Integrated real-time clock/calendar
• 4096 x 8 nonvolatile static RAM
• 120ns access time
• Automatic power-fail chip deselect and write-protection
• Lithium energy source for data retention and clock/calendar operation
• Industrial temperature range of -40°C to +85°C
• Simple multiplexed address/data bus interface
• 10 years of data retention

This product is an ideal solution for applications requiring reliable timekeeping and data storage through power loss, such as in embedded systems, industrial control systems, and other critical applications where maintaining accurate time and data integrity is paramount.