Rainbow-electronics DS12887A Bedienungsanleitung PDF herunterladen

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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

DS1287A

§ 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 Connect

MOT - Bus Type Selection

CS - RTC Chip-Select Input

AS - Address Strobe

W - Read/Write Input

DS - Data Strobe

RESET - Reset Input

IRQ - Interrupt Request Output

SQW - Square-Wave Output

- +5V Main Supply

RCLR - RAM Clear

GND - Ground

ORDERING INFORMATION

PART PIN-PACKAGE TOP MARK TEMP RANGE

DS12887A 24 PDIP Module DS12887A 0°C to +70°C

MOT

DS12887A

24 PDIP Module (700mil)

N.C.

AD1

AD3

AD4

AD5

AD6

AD7

GND

SQW

N.C.

IRQ

RESET

N.C.

R/W

N.C.

AD0

AD2

RCLR

DS12887A

Real-Time Clock

www.maxim-ic.com

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Inhaltsverzeichnis

Seite 1 - Real-Time Clock

1 of 2 073102Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any d

Seite 2 - TYPICAL OPERATING CIRCUIT

DS12887A2 of 2DESCRIPTIONThe DS12887A real-time clock plus RAM is designed to be a direct replacement for the DS1287A. TheDS12887A is identical in for