bq3285E/L
Real-Time Clock (RTC)
Features вћ¤ BCD or binary format for clock
and calendar data General Description вћ¤ Direct clock/calendar replacement for IBMВ® AT-compatible
computers and other applications вћ¤ Calendar in day of the week, day
of the month, months, and years,
with automatic leap-year adjustment The CMOS bq3285E/L is a lowpower microprocessor peripheral
providing a time-of-day clock and
100-year calendar with alarm features and battery operation. The
bq3285L supports 3V systems.
Other bq3285E/L features include
three maskable interrupt sources,
square-wave output, and 242 bytes
of general nonvolatile storage. вћ¤ Functionally compatible with the
DS1285 -Closely matches MC146818A
pin configuration вћ¤ Time of day in seconds, minutes,
and hours -➤ 2.7–3.6V operation (bq3285L);
4.5–5.5V operation (bq3285E) 12-or 24-hour format
Optional daylight saving
adjustment вћ¤ 242 bytes of general nonvolatile
storage ➤ Programmable square wave output ➤ 32.768kHz output for power management ➤ Three individually maskable interrupt event flags: ➤ System wake-up capability—
alarm interrupt output active in
battery-backup mode …