Owner manual

1 of 19 081902
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
§ Real-time clock (RTC) keeps track of
hundredths of seconds, minutes, hours, days,
date of the month, months, and years
§ 32k x 8 NV SRAM directly replaces volatile
static RAM or EEPROM
§ Embedded lithium energy cell maintains
calendar operation and retains RAM data
§ Watch function is transparent to RAM
operation
§ Month and year determine the number of
days in each month; valid up to 2100
§ Full 10% operating range
§ Operating temperature range: 0°C to +70°C
§ Over 10 years of data retention in the
absence of power
§ Lithium energy source is electrically
disconnected to retain freshness until power
is applied for the first time
§ DIP module only
§ Standard 28-pin JEDEC pinout
§ PowerCap
®
module board only
– Surface mountable package for direct
connection to PowerCap containing
battery and crystal
– Replaceable battery (PowerCap)
– Pin-for-pin compatible with DS1248P
and DS1251P
§ Underwriters Laboratory (UL) recognized
PowerCap is a registered trademark of Dallas Semiconductor.
PIN ASSIGNMENT (Top View)
Package Dimension Information
http://www.maxim-ic.com/TechSupport/DallasPackInfo.htm
DS2144
28-PDIP Module (740mil)
V
CC
WE
A
13
A
8
A
9
A
11
OE
A
10
CE
DQ7
DQ6
DQ5
DQ3
DQ4
1
2
3
4
5
6
7
8
9
10
11
12
14
13
28
27
26
25
24
23
22
21
20
19
18
17
15
16
A
14/RST
A
12
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
0
DQ0
DQ1
GND
DQ2
3
N.C.
N.C.
WE
CE
DQ7
DQ6
DQ4
DQ3
DQ1
DQ0
4
6
7
8
10
11
12
14
15
16
N.C.33
32
31
29
27
25
24
22
21
20
18
A
12
A
11
A
9
A
8
A
6
A
5
A
2
A
4
A
0
1
V
CC
28
A
1
RST
2
N.C.
OE
DQ5
DQ2
GND
5
9
13
17
A
14
30
26
23
19
A
13
A
10
A
7
A
3
34
N.C.
X1 GND
V
BAT
X2
DS1244P
34-Pin PowerCap Module
(Uses DS9034PCX PowerCap)
DS1244/DS1244P
256k NV SRAM
with Phantom Clock
www.maxim-ic.com
www.maxim-ic.com