DS17487-5

The DS17487-5 by Dallas Semiconductor is a Real-Time Clock (RTC) designed as a successor to the DS12887. This device integrates a quartz crystal and lithium energy source into a 24-pin DIP package, providing timekeeping functions including seconds, minutes, hours, day, date, month, and year with leap year compensation through 2099.

Key features include 114 bytes of general-purpose, battery-backed NV SRAM, a 64-bit silicon serial number, and power-control circuitry that allows system power-on from a keyboard or a time-and-date alarm. It supports optional +3.0V or +5.0V operation and offers selectable crystal load capacitance for 6pF or 12.5pF crystals. The RTC operates in either 12-hour or 24-hour format with an AM/PM indicator.

The DS17487-5 is suitable for applications such as embedded systems, utility meters, security systems, and network hubs. It is available in PDIP, SO, or TSOP packages, supporting through-hole mounting.

This RTC includes automatic power-fail detect and switch circuitry, ensuring time and date operation is maintained when primary power is absent. It also features a time-of-day alarm, programmable square-wave output, and six independently maskable interrupt flags.