The DS1305EN+T&R is a serial alarm real time clock in 20 pin TSSOP package. This 3-wire/SPI interface trickle charge real time clock with alarm provides full binary coded decimal (BCD) clock calendar which is accessed by simple serial interface. The clock/calendar provides seconds, minutes, hours, day, date, month and year information. The end of the month date is automatically adjusted for months with fewer than 31 days including corrections for leap year compensation valid up to 2100. The clock operates in either 24hr or 12hr format with AM/PM indicator. In addition, 96bytes of NV RAM is provided for data storage. The DS1305 will maintain time and date provided the oscillator is enabled as long as at least one supply is at a valid level. The device offers dual power supply pins for primary and backup power supplies as well as a battery input pin. The dual power supplies support programmable trickle charge circuit that allows rechargeable energy source to be used for backup supply
● Supply voltage range from 2V to 5.5V
● Operating temperature range from -40°C to 85°C
● Completely manages all timekeeping functions
● Two time of day alarms programmable on combination of seconds, minutes, hours and day of the week
● Supports SPI modes 1 and 3 or standard 3-wire interface
● Burst mode for reading/writing successive addresses in clock/RAM
● Multiple power supply pins for adding battery for backup
● Battery timekeeping current of 400nA at VBAT = 3V
● UL recognized
● VCC1 active supply current of 1.28mA & VCC1 timekeeping current of 81µA at VCC1 = 5V
