DS1747_12 Datasheet, PDF (1/16 Pages) Maxim Integrated Products – Y2K-Compliant, Nonvolatile Timekeeping RAMs

19-5504; Rev 3/12
DS1747/DS1747P
Y2K-Compliant, Nonvolatile Timekeeping RAMs
FEATURES
 Integrated NV SRAM, Real-Time Clock
(RTC), Crystal, Power-Fail Control
Circuit, and Lithium Energy Source
 Clock Registers are Accessed Identically to
the Static RAM. These Registers are
Resident in the Eight Top RAM Locations
 Century Byte Register (Y2K Compliant)
 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
Up to the Year 2100
 Battery Voltage-Level Indicator Flag
 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 Byte-Wide 512k 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
of DS174xP Timekeeping RAM
 Also Available in Industrial Temperature
Range: -40°C to +85°C
PIN CONFIGURATIONS
TOP VIEW
A18
A16
A14
A12
A7
A6
A5
A4
A3
A2
A1
A0
DQ0
DQ1
DQ2
GND
1
32
2 ^{Maxim 31}
3 ^DS1747 30
4
29
5
28
6
27
7
26
8
25
9
24
10
23
11
22
12
21
13
20
14
19
15
18
16
17
VCC
A15
A17
WE
A13
A8
A9
A11
OE
A10
CE
DQ7
DQ6
DQ5
DQ4
DQ3
Encapsulated DIP
(512k x 8)
N.C. 1
A15 2
A16 3
Maxim
DS1747P
34
A18
33
A17
32
A14
RST
4
31
A13
VCC
WE
5
6
30
A12
29
A11
OE
7
CE
DQ7
8
9
DQ6 ¹⁰
28
A10
27
A9
26
A8
25
A7
DQ5 11
DQ4 12
24
A6
23
A5
DQ3
13
22
A4
DQ2
DQ1
DQ0
GND
14
21
15
20
16
17
X1 GND VBAT X2
19
18
A3
A2
A1
A0
PowerCap Module Board
(Uses DS9034PCX+ or DS9034I-PCX+ PowerCap)
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.
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