DS1743 Datasheet, PDF (1/16 Pages) Dallas Semiconductor – Y2KC Nonvolatile Timekeeping RAM

www.maxim-ic.com
DS1743/DS1743P
Y2K-Compliant, Nonvolatile Timekeeping
RAMs
FEATURES
PIN CONFIGURATIONS
Integrated NV SRAM, Real-Time Clock,
Crystal, Power-Fail Control Circuit, and
TOP VIEW
Lithium Energy Source
Clock Registers are Accessed Identically to
the Static RAM. These Registers Reside in
the Eight Top RAM Locations.
Century Byte Register
Totally Nonvolatile with Over 10 Years of
Operation in the Absence of Power
BCD-Coded Century, Year, Month, Date,
Day, Hours, Minutes, and Seconds with
Automatic Leap Year Compensation Valid
N.C.
A12
A7
A6
A5
A4
A3
A2
A1
A0
DQ0
DQ1
DQ2
GND
1
28
2 DS1743 27
3
26
4
25
5
24
6
23
7
22
8
21
9
20
10
19
11
18
12
17
13
16
14
15
V_CC
WE
CE2
A8
A9
A11
OE
A10
CE
DQ7
DQ6
DQ5
DQ4
DQ3
through 2099
Low-Battery-Voltage Level Indicator Flag
28-Pin Encapsulated Package
(28 PIN 740)
Power-Fail Write Protection Allows for ±10%
V_CC Power-Supply Tolerance
Lithium Energy Source is Electrically
Disconnected to Retain Freshness Until
Power is Applied for the First Time
DIP Module Only
Standard JEDEC Bytewide 8k x 8 Static
RAM Pinout
PowerCap Module Board Only
Surface-Mountable Package for Direct
Connection to PowerCap Containing
Battery and Crystal
Replaceable Battery (PowerCap)
Power-On Reset Output
Pin-for-Pin Compatible with Other Densities
N.C.
N.C.
N.C.
RST
V_CC
WE
OE
CE
DQ7
DQ6
DQ5
DQ4
DQ3
DQ2
DQ1
DQ0
GND
1
2
DS1743P
34
33
3
32
4
31
5
30
6
29
7
28
8
27
9
26
10
25
11
24
12
23
13
22
14
21
15
20
16
19
17 ^{X1 GND VBAT X2} 18
N.C.
N.C.
N.C.
N.C.
A12
A11
A10
A9
A8
A7
A6
A5
A4
A3
A2
A1
A0
34-Pin PowerCap Module Board
(Uses DS9034PCX PowerCap)
of DS174XP Timekeeping RAM
Underwriters Laboratories (UL) Recognized
to Prevent Charging of the Internal Lithium
Battery
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: www.maxim-ic.com/errata.
1 of 16
REV: 090407