The DS1685SN-5+ from Maxim Integrated Products is a real time clock with +5V operation in 24 pin SOIC package. It is designed as successors to the industry standard DS1285, DS1385, DS1485 and DS1585 PC RTCs. The device provides industry standard DS1285 clock function with +5V operation. The DS1685 is a clock/calendar chip with enhanced features such as 64bit silicon serial number, power-on/off control circuitry, 242bytes of battery backed user NV SRAM and 32.768KHz output for sustaining power management activities. 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. An external crystal and battery are the only components required to maintain time of day and memory status in the absence of power. The DS1685 is used in embedded systems, utility meters, network hubs, bridges and routers. The crystal select bit allows RTC to operate with 6pF or 12.5pF crystal.
Power supply voltage range from 4.5V to 5.5V
Operating temperature range from -40°C to 85°C
Incorporates industry standard DS1287 PC clock and enhanced features such as Y2K compliant
Can be driven by an external 32.768KHz oscillator
Time keeping current of 400nA
SMI recovery stack and multiplexed interface
Auxiliary battery input, RAM clear input, century register and date alarm register
Compatible with existing BIOS for original DS1287 functions
Timekeeping algorithm includes leap year compensation valid through 2099
