DS1390U-33+ Datasheet PDF - Maxim Integrated

The DS1390U-33+ is a low voltage SPI real time clock (RTC) with trickle charger in 10 pin µSOP package. It has typical operating voltage of 3.3V. This clock/calendar provides hundredths of seconds, seconds, minutes, hours, day, date, month and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days including leap year compensation valid up to 2100. The clock operates in either 24hour or 12hour format with an AM/PM indicator. A temperature compensated voltage reference monitors the status of VCC and automatically disables bus interface and switches to backup supply if a power failure is detected. On the DS1390, a single open-drain output provides CPU interrupt or square wave at one of four selectable frequencies of 32.768KHz, 8.192KHz, 4.096KHz or 1Hz. The device is programmed serially through SPI compatible bidirectional bus. The DS1390 is used in GPS/telematics devices, embedded time stamping applications.

● Supply voltage range from 2.97V to 5.5V

● Operating temperature range from -40°C to 85°C

● Power fail detect and switch circuitry

● SPI supports modes 1 and 3

● SCLK frequency of 4MHz ( 2.7V

● UL recognized

● VCC active supply current of 2mA and VCC standby current of 115µA

● Time keeping current of 500nA

● One programmable time of day alarm