Maxim Integrated DS1391U-18+ Low-Voltage SPI/3-Wire RTCs

The DS1391U-18+ from Maxim Integrated is a highly integrated, low-voltage real-time clock (RTC) with an SPI/3-wire interface that provides a full binary-coded decimal (BCD) clock/calendar with 56 bytes of NV SRAM. This precision timekeeping device is designed for a wide range of applications in embedded systems, including networking hardware, industrial equipment, and consumer electronics where accurate timekeeping is essential.

Operating at a voltage range of 1.8V to 5.5V, the DS1391U-18+ is suitable for battery-backed applications where power consumption is critical. It ensures that timekeeping remains accurate even when the main power is lost, thanks to its integrated battery-backup input. The device also features a programmable square-wave output that can be used for various purposes, including timekeeping, alarms, or as a periodic interrupt source.

The RTC provides seconds, minutes, hours, day, date, month, and year information, with the date at the end of the month automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either 24-hour or 12-hour format with an AM/PM indicator.

Additional features of the DS1391U-18+ include a dual-purpose memory that can be used both as a scratchpad and as a non-volatile storage area, which is ideal for storing data that must be preserved during power loss. The device also has an integrated crystal that significantly reduces the number of external components and simplifies the design of the timekeeping subsystem.

With its robust feature set and low power consumption, the DS1391U-18+ is an excellent choice for designers looking for a reliable RTC solution. Its 10-pin µSOP package makes it a compact and space-saving option for modern PCB layouts. Maxim Integrated's commitment to quality ensures that the DS1391U-18+ RTC will provide long-term, accurate timekeeping in a variety of applications.

For further details, datasheets, and support resources, designers and engineers are encouraged to visit Maxim Integrated's official website or contact their local sales office.