X25021 Datasheet, PDF (1/14 Pages) Xicor Inc. – SPI Serial E2PROM with Block LockTM Protection

X25021
2K
X25021
256 x 8 Bit
SPI Serial E²PROM with Block Lock^TM Protection
FEATURES
• 1MHz Clock Rate
• SPI Modes (0,1 & 1,0)
• 256 X 8 Bits
—4 Byte Page Mode
• Low Power CMOS
—10µA Standby Current
—3mA Active Current
• 2.7V To 5.5V Power Supply
• Block Lock Protection
—Protect 1/4, 1/2 or all of E²PROM Array
• Built-in Inadvertent Write Protection
—Power-Up/Power-Down protection circuitry
—Write Latch
—Write Protect Pin
• Self-Timed Write Cycle
—5ms Write Cycle Time (Typical)
• High Reliability
—Endurance: 100,000 cycles per byte
—Data Retention: 100 Years
—ESD protection: 2000V on all pins
• 8-Lead PDlP Package
• 8-Lead SOIC Package
DESCRIPTION
The X25021 is a CMOS 2048-bit serial E²PROM, inter-
nally organized as 256 x 8. The X25021 features a Serial
Peripheral Interface (SPI) and software protocol allow-
ing 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 con-
trolled through a chip select (CS) input, allowing any
number of devices to share the same bus.
The X25021 also features two additional inputs that
provide the end user with added flexibility. By asserting
the HOLD input, the X25021 will ignore transitions on its
inputs, thus allowing the host to service higher priority
interrupts. The WP input can be used as a hardwire input
to the X25021 disabling all write attempts, thus providing
a mechanism for limiting end user capability of altering
the memory.
The X25021 utilizes Xicor’s proprietary Direct Write™
cell, providing a minimum endurance of 100,000 cycles
per byte and a minimum data retention of 100 years.
FUNCTIONAL DIAGRAM
STATUS
REGISTER
SO
SI
SCK
CS
HOLD
COMMAND
DECODE
AND
CONTROL
LOGIC
WRITE
PROTECT
LOGIC
WRITE
CONTROL
AND
WP
TIMING
LOGIC
Direct Write™ and Block Lock™ Protection is a trademark of Xicor, Inc.
©Xicor, Inc. 1995, 1996 Patents Pending
6615-1.5 6/10/96 T3/C1/D0 NS
1
X DECODE
LOGIC
16
16
32
256 BYTE
ARRAY
16 X 32
16 X 32
32 X 32
4
8
Y DECODE
DATA REGISTER
6615 FHD F01
Characteristics subject to change without notice