OVERVIEW

The SM8578BV is a serial interface, real-time clock IC that uses a 32.768 kHz crystal oscillator for its refer ence timing. It comprises second-counter to year-counter clock and calendar circuits that feature automatic leap-year adjustment, alarm and timer interrupt functions, as well as oscillator stop, timer reloading, and other detection functions. Data is transferred to and from an external controller using a 3-wire serial interface. It is available in compact 8-pin VSOP packages, making it ideal for use in all types of portable, hand-held equipment.

FEATURES

■ 1.6 to 5.5V wide operating voltage range

■ 0.5µA (typ.) current consumption (VDD = 3.0V, CE = Low)

■ 3-wire serial interface control

■ Day, day-of-week, hour, and minute alarm interrupt function

■ 1/4096 seconds to 255 minutes presettable interval timer interrupt function

■ Time update detection function

■ Abnormal oscillation detection function

■ Automatic leap-year adjustment function (Western and Japanese calendars)

■ Oscillator capacitor CD built-in

■ Molybdenum-gate CMOS process

■ Miniature 8-pin VSOP package