DS12887A Datasheet Download

Part No.:
DS12887A
Download:
Download Datasheet
Description:
[Real-Time Clock]
File Size:
179 K
Page:
2 Pages
Logo:
Manufacturer:
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
PCB Prototype
 DS12887A Datasheet Page:2 
www.maxim-ic.com
DS12887A
Real-Time Clock
PIN ASSIGNMENT (Top View)
MOT
N.C.
N.C.
AD0
AD1
AD2
AD3
AD4
AD5
AD6
AD7
GND
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
V
CC
SQW
NC
RCLR
N.C.
IRQ
RESET
DS
N.C.
R/W
AS
CS
www.maxim-ic.com
FEATURES
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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
Package Dimension Information
PIN DESCRIPTION
AD0–AD7 - Multiplexed Address/Data Bus
N.C.
- No Connect
MOT
- Bus Type Selection
CS
- RTC Chip-Select Input
AS
- Address Strobe
- Read/Write Input
R/
W
DS
- Data Strobe
RESET
- Reset Input
IRQ
- Interrupt Request Output
SQW
- Square-Wave Output
V
CC
- +5V Main Supply
RCLR
- RAM Clear
GND
- Ground
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ORDERING INFORMATION
PART
PIN-PACKAGE
DS12887A 24 PDIP Module
TOP MARK
DS12887A
TEMP RANGE
0°C to +70°C
Note:
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