X24640 Datasheet, PDF (1/17 Pages) Xicor Inc. – 400KHz 2-Wire Serial E 2 PROM with Block Lock

64K
X24640
8K x 8 Bit
400KHz 2-Wire Serial E²PROM with Block Lock^TM
FEATURES
• Save Critical Data with Programmable
Block Lock Protection
—Block Lock (0, 1/4, 1/2, or all of E²PROM Array)
—Software Program Protection
—Programmable Hardware Write Protect
• In Circuit Programmable ROM Mode
• 400KHz 2-Wire Serial Interfac
—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 Program 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
• 32 Word Page Write Mode
—Minimizes Total Write Time Per Word
• Internally Organized 8K x 8
• Bidirectional Data Transfer Protocol
• Self-Timed Write Cycle
—Typical Write Cycle Time of 5ms
• High Reliability
—Endurance: 100,000 Cycles
—Data Retention: 100 Years
• 8-Lead SOIC
• 20-Lead TSSOP
• 8-Lead PDIP
FUNCTIONAL DIAGRAM
DESCRIPTION
The X24640 is a CMOS Serial E²PROM, internally
organized 8K x 8. The device features a serial inter-
face and software protocol allowing operation on a
simple two wire bus. The bus operates at 400 KHz all
the way down to 1.8V.
Three device select inputs (S₀–S₂) allow up to eight
devices to share a common two wire bus.
A Write Protect Register at the highest address loca-
tion, 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 Hardware Write Protect feature
allows the user to install the device with WP tied to
V_CC, program and Block Lock the desired portions of
the memory array in circuit, and then enable the In
Circuit Programmable ROM Mode by programming the
WPEN bit in the Write Protect Register. After this, the
Block Locked portions of the array, including the Write
Protect Register itself, are permanently protected from
being erased.
SERIAL E²PROM DATA
AND ADDRESS (SDA)
DATA REGISTER
Y DECODE LOGIC
SCL
COMMAND
DECODE
AND
CONTROL
LOGIC
PAGE
DECODE
LOGIC
BLOCK LOCK AND
WRITE PROTECT
CONTROL LOGIC
S2
DEVICE
S1
SELECT
LOGIC
S0
WRITE
PROTECT
REGISTER
SERIAL E²PROM
ARRAY
8K x 8
2K x 8
2K x 8
4K x 8
WP
©Xicor, 1995, 1996 Patents Pending
7038-1.2 4/25/97 T0/C2/D0 SH
WRITE VOLTAGE
CONTROL
7038 FM 01
Characteristics subject to change without notice
1