DS1254
2M x 8 NV SRAM with Phantom Clock
www.maxim-ic.com
FEATURES
§ Real-time clock (RTC) keeps track of hundredths
of seconds, seconds, minutes, hours, days, date,
months, and years with automatic leap-year
compensation valid up to the year 2100
§ 2M x 8 NV SRAM
§ Watch function is transparent to RAM operation
§ Automatic data protection during power loss
§ Unlimited write-cycle endurance
§ Surface-mountable BGA module construction
§ Over 10 years of data retention in the absence of
power
§ Battery monitor checks remaining capacity daily
§ +3.3V or +5V operation
APPLICATIONS
Telecom Switches
Routers
RAID Systems
TYPICAL OPERATING CIRCUIT
PACKAGE OUTLINE
Side -A- Shown
(For Reference Only, Not to Scale)
Component placement may vary.
ORDERING INFORMATION
PART
DS1254WB-
150
DS1254YB-
100
DS1254WB2-
150
DS1254YB2-
100
PIN-
PACKAGE
BGA, 3.3V
BGA, 5V
BGA, 3.3V
BGA, 5V
TEMP
RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
TOP
MARK
DS1254W-
150
DS1254Y-
100
DS1254W2-
150
DS1254Y2-
100
PIN DESCRIPTION
VCC
A0–A20
- Supply Voltage
- Address Inputs
DQ0–DQ7 - Data I/O
CE
- Chip-Enable Input
OE
- Output-Enable Input
WE
- Write-Enable Input
BW
- Battery Warning Output
(Open Drain)
GND
- Ground
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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