DS1746_10 Datasheet, PDF (1/16 Pages) Maxim Integrated Products – Y2K-Compliant, Nonvolatile Timekeeping RAMs

19-5503; Rev 9/10
DS1746/DS1746P
Y2K-Compliant, Nonvolatile Timekeeping RAMs
www.maxim-ic.com
FEATURES
 Integrated NV SRAM, Real-Time Clock,
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 (i.e., 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 128k 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
 Underwriters Laboratories (UL) recognized
PIN CONFIGURATIONS
TOP VIEW
N.C.
A16
A14
A12
A7
A6
A5
A4
A3
A2
A1
A0
DQ0
DQ1
DQ2
GND
1
32
2 ^{Maxim 31}
3 ^DS1746 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
V_CC
A15
N.C.
WE
A13
A8
A9
A11
OE
A10
CE
DQ7
DQ6
DQ5
DQ4
DQ3
Encapsulated DIP
N.C. ₁
A15 ₂
34
Maxim
33
A16 ₃
RST 4
DS1746P
32
31
V_WCEC
5
6
30
29
OE ⁷
28
CE ⁸
DQ7 ⁹
27
26
DQ6 ¹⁰
25
DQ5 ¹¹
DQ4 ¹²
24
23
DQ3 ¹³
22
DQ2 ¹⁴
21
DQ1
DQ0
GND
15
16
17
20
19
X1 GND V_BAT X2
18
N.C.
N.C.
A14
A13
A12
A11
A10
A9
A8
A7
A6
A5
A4
A3
A2
A1
A0
PowerCap Module Board
(Uses DS9034PCX 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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