32K
4Kx 8 Bit
X24320
400KHz 2-Wire Serial E2PROM with Block Lock™
DESCRIPTION
FEATURES
• Save Critical Data with Programmable Block
Lock Protection
The X24320 is a CMOS Serial E2PROM, internally
organized 4K x 8.The device features a serial interface
and software protocol allowing operation on a simple
two wire bus. The bus operates at 400 KHz all the way
down to 1.8V.
—Block lock (0, 1/4, 1/2, or all of E2PROM array)
—Software write protection
—Programmable hardware write protect
• In Circuit Programmable ROM Mode
• 400KHz 2-Wire Serial Interface
—Schmitt trigger input noise suppression
—Output slope control for ground bounce noise
elimination
• Longer Battery Life With Lower Power
—Active read current less than 1mA
—Active write current less than 3mA
—Standby current less than 1µA
• 1.8V to 3.6V, 2.5V to 5.5V and 4.5V to 5.5V Power
Supply Versions
Three device select inputs (S –S ) allow up to eight
0
2
devices to share a common two wire bus.
A Write Protect Register at the highest address location,
FFFFh, provides three write protection features: Software
Write Protect, Block Lock Protect, and Programmable
Hardware Write Protect. The Software Write Protect
feature prevents any nonvolatile writes to the device
until the WEL bit in the Write Protect Register is set.
The Block Lock Protection feature gives the user four
array block protect options, set by programming two bits
in the Write Protect Register. The Programmable Hard-
ware Write Protect feature allows the user to install the
• 32 Word Page Write Mode
—Minimizes total write time per word
• Internally Organized 4K x 8
• Bidirectional Data Transfer Protocol
• Self-Timed Write Cycle
—Typical write cycle time of 5ms
• High Reliability
—Endurance: 1 million cycles
—Data retention: 100 years
• 8-Lead SOIC
device with WP tied to V , write to and Block Lock the
CC
desired portions of the memory array in circuit, and then
enable the In Circuit Programmable ROM Mode by pro-
gramming the WPEN bit HIGH in the Write Protect Reg-
ister. After this, the Block Locked portions of the array,
including the Write Protect Register itself, are perma-
nently protected from being erased.
Xicor E2PROMs are designed and tested for applica-
tions requiring extended endurance. Inherent data
retention is greater than 100 years.
• 14-Lead TSSOP
—8-Lead PDIP
BLOCK DIAGRAM
Data Register
Serial E2PROM Data
and Address (SDA)
Y Decode Logic
Serial E2PROM
Command
SCL
Decode
and
Array
Page
Decode
Logic
4K x 8
Control
Logic
1K x 8
1K x 8
Block Lock and
Write Protect
Control Logic
S
S
S
2
1
0
Device
Select
Logic
Write
Protect
Register
2K x 8
Write Voltage
Control
WP
Xicor, Inc. 2000 Patents Pending
7035-1.2 10/27/00 EP
Characteristics subject to change without notice. 1 of 18