DS 1687-5 – Echtzeituhr, Uhr/Kalender, DIL-24

The DS1685/DS1687 are real-time clocks (RTC) designe d as successors to the industry-standard DS1285, DS1385, DS1485, and DS1585 PC RTCs. These devices prov ide the industry-standard DS1285 clock function with either +3.0V or +5.0V operation. The DS1685 also incorp orates a number of enhanced features including a silicon serial number, power-on/off control circuitry, 242 byte s of user NV SRAM, and 32.768kHz output for sustaining power management activities. The DS1685/DS1687 power-control circuitry allows the system to be powered on by an external stimulus such as a keyboard or by a time and date (wake-up) alarm. The PW R output pin can be triggered by one or either of these events, and can be used to turn on an external power supply. The PWR pin is under software control, so that when a task is complete, the system power can then be shut down.