19-5589; Rev 10/10
DS1345Y/AB
1024k Nonvolatile SRAM
with Battery Monitor
www.maxim-ic.com
FEATURES
PIN ASSIGNMENT
. 10 years minimum data retention in the
absence of external power
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
NC
NC
A14
1
2
3
4
5
6
7
8
9
BW
.
Data is automatically protected during power
loss
A15
A16
RST
VCC
A13
A12
A11
A10
A9
. Power supply monitor resets processor when
CC power loss occurs and holds processor in
WE
OE
V
CE
A8
DQ7
reset during VCC ramp-up
A7
A6
A5
A4
A3
A2
A1
A0
10
11
12
13
14
15
DQ6
DQ5
DQ4
DQ3
DQ2
DQ1
DQ0
GND
. Battery monitor checks remaining capacity
daily
GND VBAT
. Read and write access times of 70ns
. Unlimited write cycle endurance
. Typical standby current 50µA
. Upgrade for 128k x 8 SRAM, EEPROM or
Flash
16
17
34-Pin PowerCap Module (PCM)
(Uses DS9034PC+ or DS9034PCI+ PowerCap)
. Lithium battery is electrically disconnected to
retain freshness until power is applied for the
first time
. Full ±10% VCC operating range (DS1345Y)
or optional ±5% VCC operating range
(DS1345AB)
. Optional industrial temperature range of
-40°C to +85°C, designated IND
. PowerCap Module (PCM) package
PIN DESCRIPTION
A0 – A16
DQ0 – DQ7
CE
- Address Inputs
- Data In/Data Out
- Chip Enable
- Write Enable
- Output Enable
- Reset Output
- Battery Warning Output
- Power (+5V)
- Ground
WE
OE
RST
BW
VCC
GND
NC
-
-
Directly surface-mountable module
Replaceable snap-on PowerCap provides
lithium backup battery
- No Connect
-
-
Standardized pinout for all nonvolatile
(NV) SRAM products
Detachment feature on PowerCap allows
easy removal using a regular screwdriver
DESCRIPTION
The DS1345 1024k NV SRAMs are 1,048,576-bit, fully static, NV SRAMs organized as 131,072 words
by 8 bits. Each NV SRAM has a self-contained lithium energy source and control circuitry which
constantly monitors VCC for an out-of-tolerance condition. When such a condition occurs, the lithium
energy source is automatically switched on and write protection is unconditionally enabled to prevent
data corruption. Additionally, the DS1345 devices have dedicated circuitry for monitoring the status of
VCC and the status of the internal lithium battery. DS1345 devices in the PowerCap module package are
directly surface mountable and are normally paired with a DS9034PC PowerCap to form a complete NV
SRAM module. The devices can be used in place of 128k x 8 SRAM, EEPROM, or Flash components.
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