TM
ICmic
8K x 8 Bit
This X25642 device has been acquired by
IC MICROSYSTEMS from Xicor, Inc.
IC MICROSYSTEMS
64K
X25642
2
TM
Advanced SPI Serial E PROM with Block Lock Protection
FEATURES
DESCRIPTION
The X25642 is a CMOS 65,536-bit serial E2PROM,
internally organized as 8K x 8. The X25642 features a
•2MHz Clock Rate
•Low Power CMOS
—<1µA Standby Current
—<5mA Active Current
•2.7V To 5.5V Power Supply
Serial Peripheral Interface (SPI) and software protocol
allowing operation on a simple three-wire bus. The bus
signals are a clock input (SCK) plus separate data in (SI)
and data out (SO) lines. Access to the device is
•SPI Modes (0,0 & 1,1)
•8K X 8 Bits
—32 Byte Page Mode
controlled through a chip select (CS) input, allowing any
number of devices to share the same bus.
•Block Lock Protection
—Protect 1/4, 1/2 or all of E2PROM Array
•Built-in Inadvertent Write Protection
—Power-Up/Down protection circuitry
—Write Enable Latch
The X25642 also features two additional inputs that
provide the end user with added flexibility. By
asserting the HOLD input, the X25642 will ignore tran-
sitions on its inputs, thus allowing the host to service
higher priority interrupts. The WP input can be used as a
hardwire input to the X25642 disabling all write
—Write Protect Pin
•Self-Timed Write Cycle
—5ms Write Cycle Time (Typical)
•High Reliability
—Endurance: 100,000 cycles
—Data Retention: 100 Years
—ESD protection: 2000V on all pins
•Packages
attempts to the status register, thus providing a mech-
anism for limiting end user capability of altering 0, 1/4,
1/2 or all of the memory.
The X25642 utilizes Xicor’s proprietary Direct WriteTM cell,
providing a minimum endurance of 100,000
cycles and a minimum data retention of 100 years.
—8-Lead PDIP
—8-Lead SOIC
—14-Lead SOIC
—20-Lead TSSOP
FUNCTIONAL DIAGRAM
WRITE
PROTECT
LOGIC
STATUS
REGISTER
X DECODE
LOGIC
8K BYTE
ARRAY
64
64
64 X 256
64 X 256
SO
SI
COMMAND
DECODE
SCK
AND
CONTROL
LOGIC
CS
HOLD
128
128 X 256
WRITE
CONTROL
AND
TIMING
LOGIC
WP
32
8
Y DECODE
DATA REGISTER
3132 ILL F01.1
Direct WriteTM and Block Lock ProtectionTM is a trademark of Xicor, Inc.
©Xicor, Inc. 1994, 1995, 1996 Patents Pending
1
Characteristics subject to change without notice
3132-1.0 1/17/97 T5/C0/D1 SH
ICMIC [ IC MICROSYSTEMS ]
