Rainbow Electronics DS1687 - 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
Incorporates industry-standard DS1287 PC clock
plus enhanced features:
§ Y2K-compliant
§ +3 or +5V operation
§ 64-bit silicon serial number
§ Power-control circuitry supports system
power-on from date/time alarm or key
closure
§ 32kHz output for power management
§ Crystal-select bit allows RTC to operate with
6pF or 12.5pF crystal
§ SMI Recovery Stack
§ 242 bytes user NV RAM
§ Auxiliary battery input
§ RAM clear input
§ Century register
§ Date alarm register
§ Compatible with existing BIOS for original
DS1287 functions
§ Available as chip (DS1685) or standalone
module with embedded battery and crystal
(DS1687)
PIN ASSIGNMENT (Top View)
§ Timekeeping algorithm includes leap-year
compensation valid up to 2100
§ Underwriters Laboratory (UL) recognized
Package Dimension Information
http://www.maxim-ic.com/TechSupport/DallasPackInfo.htm
1
2
3
4
5
6
7
8
9
10
24
23
22
21
20
19
18
17
16
15
V
CC
SQW
V
BAUX
RCLR
N.C.
IRQ
KS
RD
NC
WR
PWR
N.C.
N.C.
AD0
AD1
AD2
AD3
AD4
AD5
AD6
DS1687 24-Pin Module PDIP (740mil)
11
12
14
13
AD7
GND
ALE
CS
1
2
3
4
5
6
7
8
9
10
24
23
22
21
20
19
18
17
16
15
V
CC
SQW
V
BAUX
RCLR
V
BAT
IRQ
KS
RD
GND
WR
PWR
X1
X2
AD0
AD1
AD2
AD3
AD4
AD5
AD6
DS1685 24-Pin DIP
DS1685S 24-Pin SO (300mil)
DS1685E 24-Pin TSSOP
11
12
14
13
AD7
GND
ALE
CS
X2 X1 PW
R
N.
C.
V
CC
SQ
W
DS1685Q 28-Pin PLCC
AD0
AD1
AD2
AD3
AD4
AD5
RCLR
V
BAT
IRQ
KS
RD
GND
N.C. WR
AD
6
N.
C.
AD
7
GND
CS AL
E
NC
25
24
23
22
21
20
19
5
6
7
8
9
10
11
4 3 2 1 28 27 26
12 13 14 15 16 17 18
V
B
AUX
DS1685/DS1687
3V/5V Real-Time Clock
www.maxim-ic.com
www.maxim-ic.com