The DS1308U-33+ is a low current I2C RTC with 56byte NV RAM in 8 pin µSOP package. This serial real-time clock (RTC) is a full binary coded decimal (BCD) clock/calendar plus 56bytes of NV RAM. Address and data are transferred serially through an I2C interface. The clock/calendar provides seconds, minutes, hours, day, date, month and year information. The end of month date is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24 hour or 12 hour format with an AM/PM indicator. It has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time and date operation. It is used in office equipment (fax/printer, copier), telecommunications (router, switcher, server) and other (utility meter, vending machine, thermostat, modem).
● Supply voltage range is 3V to 5.5V
● Operating temperature range from -40°C to 85°C
● Compatible with crystal ESR up to 100Kohm allows crystal to be optimized for cost & space
● Low power operation extends battery backup run time, low timekeeping current of 250nA (typ)
● Power fail trip point is 2.82V
● Completely manages all timekeeping functions
● 56 byte, battery backed, general-purpose RAM with unlimited writes
● Programmable square wave output signal
● Simple serial port interfaces with most microcontrollers
● UL recognized
