Rainbow Electronics DS12887 - Manual

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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:
http://www.maxim-ic.com/errata .
FEATURES
§ Drop-in replacement for IBM AT computer
clock/calendar
§ Pin-compatible with the MC146818B and
DS1287
§ Totally nonvolatile with over 10 years of
operation in the absence of power
§ Self-contained subsystem includes lithium,
quartz, and support circuitry
§ 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 122ms to 500ms
– End-of-clock update cycle
§ Underwriters Laboratory (UL) recognized
PIN ASSIGNMENT (Top View)
Package Dimension Information
http://www.maxim-ic.com/TechSupport/DallasPackInfo.htm
PIN DESCRIPTION
AD0–AD7 – Multiplexed Address/Data Bus
N.C. – No Connection
MOT – Bus Type Selection
CS – Chip Select
AS – Address Strobe
R/ W – Read/Write Input
DS – Data Strobe
RESET – Reset Input
IRQ – Interrupt Request Output
SQW – Square-Wave Output
V
CC
– +5V Supply
GND – Ground
ORDERING INFORMATION
PART PIN-PACKAGE TOP MARK TEMP RANGE
DS12887 24 PDIP Module DS12887 0°C to +70°C
NC
DS12887
Real-Time Clock
www.maxim-ic.com
www.maxim-ic.com
DS12887 24 PDIP Module (700mil)