www.maxim-ic.com
DS12885/DS12885Q/DS12885T
Real-Time Clock
PIN ASSIGNMENT (Top View)
www.maxim-ic.com
FEATURES
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Drop- in replacement for IBM AT computer
clock/calendar
Pin configuration closely matches
MC146818B and DS1285
Counts seconds, minutes, hours, days, day of
the week, date, month, and year with leap-
year compensation valid up to 2100
Binary or BCD representation of time,
calendar, and alarm
12-hour or 24-hour clock with AM and PM in
12-hour mode
Daylight Savings Time option
Selectable between Motorola and Intel bus
timing
Multiplex bus for pin efficiency
Interfaced with software as 128 RAM
locations
14 bytes of clock and control registers
114 bytes of general purpose RAM
Programmable square-wave output signal
bus-compatible interrupt signals (
IRQ
)
Three interrupts are separately software-
maskable and testable
Time-of-day alarm once/second to once/day
Periodic rates from 122µs to 500ms
End-of-clock update cycle
Optional 28-pin PLCC surface mount package
or 32-pin TQFP
Optional industrial temperature range
available
Underwriters Laboratory (UL) recognized
Package Dimension Information
Note:
Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
may be simultaneously available through various sales channels. For information about device errata, click here:
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072902
DALLAS [ DALLAS SEMICONDUCTOR ]
