MAXIM DS2045W Technical data
General Description
The DS2045W is a 1Mb reflowable nonvolatile (NV)
SRAM, which consists of a static RAM (SRAM), an NV
controller, and an internal rechargeable manganese
lithium (ML) battery. These components are encased in
a surface-mount module with a 256-ball BGA footprint.
Whenever VCCis applied to the module, it recharges the
ML battery, powers the SRAM from the external power
source, and allows the contents of the SRAM to be modified. When V
CC
is powered down or out of tolerance,
the controller write-protects the SRAM’s contents and
powers the SRAM from the battery. The DS2045W also
contains a power-supply monitor output, RST, which can
be used as a CPU supervisor for a microprocessor.
Applications
RAID Systems and Servers POS Terminals
Industrial Controllers Data-Acquisition Systems
Gaming Fire Alarms
Router/Switches PLC
Features
♦ Single-Piece, Reflowable, 27mm2PBGA Package
Footprint
♦ Internal ML Battery and Charger
♦ Unconditionally Write-Protects SRAM when V
CC
is Out-of-Tolerance
♦ Automatically Switches to Battery Supply when
V
CC
Power Failures Occur
♦ Internal Power-Supply Monitor Detects Power Fail
Below Nominal V
CC
(3.3V)
♦ Reset Output can be used as a CPU Supervisor
for a Microprocessor
♦ Industrial Temperature Range (-40°C to +85°C)
♦ UL Recognized
DS2045W
DS2045W 3.3V Single-Piece 1Mb
Nonvolatile SRAM
______________________________________________ Maxim Integrated Products 1
Rev 1; 1/05
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Ordering Information
Pin Configuration appears at end of data sheet.
PART TEMP RANGE PIN-PACKAGE
SUPPLY TOLERANCE (%)
DS2045W-100 -40°C to +85°C 256 Ball 27mm
2
BGA Module
100 3.3V ±0.3V
Typical Operating Circuit
P4.0
P3.6
P3.7
P1.0–7
AD0–AD7
P4.4
P2.0–7
P3.2
RST
A8–15
A0–7
A16
DQ0–7
OE
WE
CE
8 BITS
8 BITS
8 BITS
(CE0)
(INT0)
8051
MICROPROCESSOR
DS2045W
128k x 8
NV SRAM
(WR)
(RD)
查询DS2045W供应商
SPEED (ns)
DS2045W
DS2045W 3.3V Single-Piece 1Mb
Nonvolatile SRAM
2 _____________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
RECOMMENDED OPERATING CONDITIONS
(TA= -40°C to +85°C)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
Voltage on Any Pin Relative to Ground .................-0.3V to +4.6V
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range ...............................-40°C to +85°C
Soldering Temperature...................See IPC/JEDEC J-STD-020C
PARAMETER
CONDITIONS
Supply Voltage V
CC
3.0 3.3 3.6 V
Input Logic 1 V
IH
2.2
V
Input Logic 0 V
IL
0 0.4 V
CAPACITANCE
(TA= +25°C)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Input Capacitance C
IN
Not tested 7 pF
Input/Output Capacitance C
OUT
Not tested 7 pF
DC ELECTRICAL CHARACTERISTICS
(VCC= 3.3V ±0.3V, TA= -40°C to +85°C.)
PARAMETER
CONDITIONS
UNITS
Input Leakage Current I
IL
µA
I/O Leakage Current I
IO
CE = V
CC
µA
Output-Current High I
OH
At 2.4V
mA
Output-Current Low I
OL
At 0.4V 2.0 mA
Output-Current Low RST
At 0.4V (Note 1)
mA
I
CCS1
CE = 2.2V 0.5 7
Standby Current
I
CCS2
CE = V
CC
- 0.2V 0.2 5
mA
Operating Current I
CCO1tRC
= 200ns, outputs open 50 mA
Write Protection Voltage V
TP
2.8 2.9 3.0 V
SYMBOL
SYMBOL
MIN TYP MAX UNITS
V
CC
MIN TYP MAX
-1.0 +1.0
-1.0 +1.0
-1.0
IOL RST
10.0
DS2045W
DS2045W 3.3V Single-Piece 1Mb
Nonvolatile SRAM
_____________________________________________________________________ 3
POWER-DOWN/POWER-UP TIMING
(TA= -40°C to +85°C)
PARAMETER
SYMBOL
CONDITIONS
UNITS
VCC Fail Detect to CE and WE Inactive t
PD
(Note 7) 1.5 µs
VCC Slew from VTP to 0V t
F
µs
VCC Slew from 0V to V
TP
t
R
µs
VCC Valid to CE and WE Inactive t
PU
2ms
VCC Valid to End of Write Protection t
REC
125 ms
VCC Fail Detect to RST Active t
RPD
(Note 1) 3.0 µs
VCC Valid to RST Inactive t
RPU
(Note 1)
525 ms
DATA RETENTION
(TA= +25°C)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Expected Data-Retention Time (Per Charge) t
DR
(Note 8) 2 3
years
AC ELECTRICAL CHARACTERISTICS
(VCC= 3.3V ±0.3V, TA= -40°C to +85°C.)
DS2045W-100
PARAMETER
CONDITIONS
MIN MAX
UNITS
Read Cycle Time
t
RC
100 ns
Access Time
t
ACC
100 ns
OE to Output Valid
t
OE
50 ns
CE to Output Valid
t
CO
100 ns
OE or CE to Output Active
t
COE
(Note 2) 5 ns
Output High Impedance from
Deselection
t
OD
(Note 2) 35 ns
Output Hold from Address Change
t
OH
5ns
Write Cycle Time
t
WC
100 ns
Write Pulse Width
t
WP
(Note 3) 75 ns
Address Setup Time
t
AW
0ns
t
WR1
(Note 4) 5
Write Recovery Time
t
WR2
(Note 5) 20
ns
Output High Impedance from WE
t
ODW
(Note 2) 35 ns
Output Active from WE
t
OEW
(Note 2) 5 ns
Data Setup Time
t
DS
(Note 6) 40 ns
t
DH1
(Note 4) 0
Data Hold Time
t
DH2
(Note 5) 20
ns
SYMBOL
MIN TYP MAX
150
150
225 350
DS2045W
DS2045W 3.3V Single-Piece 1Mb
Nonvolatile SRAM
4 _____________________________________________________________________
Read Cycle
OUTPUT
DATA VALID
t
RC
t
ACC
t
CO
t
OE
t
OH
t
OD
t
OD
t
COE
t
COE
V
IH
V
IH
V
IL
V
OH
V
OL
V
OH
V
OL
V
IL
V
IH
ADDRESSES
CE
OE
D
OUT
(SEE NOTE 9.)
V
IH
V
IH
V
IH
V
IH
V
IL
V
IL
V
IL
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