Preliminary Information
32K
X24325
4096 x 8 Bit
Advanced 2-Wire Serial E2PROM with Block LockTM Protection
FEATURES
• 2.7V to 5.5V Power Supply
• Low Power CMOS
—Active Read Current Less Than 1mA
—Active Write Current Less Than 3mA
—Standby Current Less Than 1µA
• Internally Organized 4096 x 8
• New Programmable Block Lock Protection
—Software Write Protection
—Programmable hardware Write Protect
• Block Lock (0, 1/4, 1/2, or all of the E2PROM
array)
• 2 Wire Serial Interface
• Bidirectional Data Transfer Protocol
• 32 Byte Page Write Mode
—Minimizes Total Write Time Per Byte
• Self Timed Write Cycle
—Typical Write Cycle Time of 5ms
• High Reliability
—Endurance: 100,000 Cycles
—Data Retention: 100 Years
• Available Packages
—8-Lead PDIP
—8-Lead SOIC (JEDEC)
—14-Lead TSSOP
FUNCTIONAL DIAGRAM
WP
VCC
VSS
SDA
START
STOP
LOGIC
DESCRIPTION
The X24325 is a CMOS 32,768 bit serial E2PROM,
internally organized 4096 x 8. The X24325 features a
serial interface and software protocol allowing opera-
tion on a simple two wire bus.
Three device select inputs (S0, S1, S2) allow up to
eight devices to share a common two wire bus.
A Write Protect Register at the highest address loca-
tion, FFFh, provides three new write protection
features: Software Write Protect, Block Write Protect,
and Hardware Write Protect. The Software Write
Protect feature prevents any nonvolatile writes to the
X24325 until the WEL bit in the write protect register is
set. The Block Write Protection feature allows the user
to individually write protect four blocks of the array by
programming two bits in the write protect register. The
Programmable Hardware Write Protect feature allows
the user to install the X24325 with WP tied to VCC,
program the entire memory array in place, and then
enable the hardware write protection by programming
a WPEN bit in the write protect register. After this,
selected blocks of the array, including the write protect
register itself, are permanently write protected.
Xicor E2PROMs are designed and tested for applica-
tions requiring extended endurance. Inherent data
retention is greater than 100 years.
START CYCLE
H.V. GENERATION
TIMING &
CONTROL
WRITE PROTECT
REGISTER AND
LOGIC
SCL
S0
S1
S2
SLAVE ADDRESS
REGISTER
+COMPARATOR
CONTROL
LOGIC
LOAD
INC
WORD
ADDRESS
COUNTER
R/W
DOUT
ACK
PIN
XDEC
E2PROM
128 X 256
YDEC
8
CK DATA REGISTER DOUT
6552 ILL F01.1
©Xicor, 1995, 1996 Patents Pending
6552-2.4 5/13/96 T1/C10/D0 NS
Characteristics subject to change without notice
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