Rev 2; 10/06
3.3V Single-Piece 4Mb Nonvolatile SRAM
with Clock
The DS3050W consists of a static RAM, a nonvolatile
(NV) controller, a year 2000-compliant real-time clock
(RTC), and an internal rechargeable manganese lithium
(ML) battery. These components are encased in a surface-mount module with a 256-ball BGA footprint.
Whenever VCC is applied to the module, it recharges
the ML battery, powers the clock and SRAM from the
external power source, and allows the contents of the
clock registers or SRAM to be modified. When VCC is
powered down or out-of-tolerance, the controller writeprotects the memory contents and powers the clock
and SRAM from the battery. The DS3050W also contains a power-supply monitor output (RST), as well as a
user-programmable interrupt output (IRQ/FT).
Applications
Features
o Single-Piece, Reflowable, 27mm x 27mm BGA
Package Footprint
o Internal Manganese Lithium Battery and Charger
o Integrated Real-Time Clock
o Unconditionally Write-Protects the Clock and
SRAM when VCC is Out-of-Tolerance
o Automatically Switches to Battery Supply when
VCC Power Failures Occur
o Reset Output can be Used as a CPU Supervisor
o Interrupt Output can be Used as a CPU Watchdog
Timer
RAID Systems and Servers
Gaming
POS Terminals
Fire Alarms
o Industrial Temperature Range (-40°C to +85°C)
Industrial Controllers
PLCs
o UL Recognized
Data-Acquisition Systems
Routers/Switches
Ordering Information
PART
DS3050W-100#
TEMP RANGE
PIN-PACKAGE
SPEED
SUPPLY VOLTAGE
-40°C to +85°C
256-ball 27mm x 27mm BGA Module
100ns
3.3V ±0.3V
#Denotes a RoHS-compliant device that may include lead that is exempt under the RoHS requirements.
Typical Operating Circuit
CE
CE
WR
WE
RD
OE
CS
CS
DS3050W
MICROPROCESSOR
OR DSP DATA
8 BITS
DQ0–7
ADDRESS
19 BITS
A0–18
INT
IRQ/FT
INT
512k x 8
NV SRAM
AND RTC
RST
Pin Configuration appears at end of data sheet.
______________________________________________ Maxim Integrated Products
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.
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DS3050W
General Description