Advanced 2-Wire Serial E
2
PROM with Block Lock
TM
Protection
32K
4096 x 8 Bit
Preliminary Information
Xicor, 1995, 1996 Patents Pending
6552-2.4 5/13/96 T1/C10/D0 NS
1
Characteristics subject to change without notice
X24325
FUNCTIONAL DIAGRAM
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 1 µ A
•
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 E
2
PROM
array)
•
2 Wire Serial Interface
•
Bidirectional Data Transfer Protocol
•
32 Byte Page Write Mode
—Minimizes T otal 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
DESCRIPTION
The X24325 is a CMOS 32,768 bit serial E
2
PROM,
internally organized 4096 x 8. The X24325 features a
serial interface and software protocol allowing operation on a simple two wire bus.
Three device select inputs (S
0
, S
1
, S
2
) 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 V
CC
,
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 E
2
PROMs are designed and tested for applications requiring extended endurance. Inherent data
retention is greater than 100 years.