900,000+ datasheet pdf search and download

Datasheet4U offers most rated semiconductors data sheet pdf






Xicor

X24257 Datasheet Preview

X24257 Datasheet

400kHz 2-Wire Serial EEPROM

No Preview Available !

www.DataSheet4U.com
Preliminary Information
256K
X24257
400kHz 2-Wire Serial EEPROM with Block Lock
32K x 8 Bit
FEATURES
• Save critical data with programmable block lock
protection
—Block lock (first page, first 2 pages, first 4
pages, first 8 pages, 1/4, 1/2, or all of EEPROM
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 1µA
—Active write current less than 3µA
—Standby current less than 1µA
• 2.5V to 5.5V power supply
• 64-byte page write mode
—Minimizes total write time per word
• Internally organized 32K 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 XBGA, 8-lead SOIC, 14-lead TSSOP
DESCRIPTION
The X24257 is a CMOS Serial EEPROM, internally
organized 32K x 8. The device features a serial inter-
face and software protocol allowing operation on a
simple two wire bus.
Three device select inputs (S0–S1) allow up to four
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 eight
array block protect options, set by programming three
bits in the Write Protect Register. The Programmable
Hardware Write Protect feature allows the user to
install the device with WP tied to VCC, write to 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 HIGH in the
Write Protect Register. After this, the Block Locked
portions of the array, including the Write Protect Register
itself, are protected from being erased if WP is high.
Xicor EEPROMs are designed and tested for applica-
tions requiring extended endurance. Inherent data
retention is greater than 100 years.
BLOCK DIAGRAM
Serial EEPROM Data
and Address (SDA)
SCL
S1
S0
Command
Decode
and
Control
Logic
Block Lock and
Write Protect
Control Logic
Device
Select
Logic
Page
Decode
Logic
Write
Protect
Register
WP
Data Register
Y Decode Logic
Serial EEPROM
Array
32K X 8
Write Voltage
Control
REV 1.1.1 10/15/00
www.xicor.com
Characteristics subject to change without notice. 1 of 19




Xicor

X24257 Datasheet Preview

X24257 Datasheet

400kHz 2-Wire Serial EEPROM

No Preview Available !

www.DataSheet4U.com
X24257 – Preliminary Information
PIN DESCRIPTIONS
Serial Clock (SCL)
The SCL input is used to clock all data into and out of
the device.
Serial Data (SDA)
SDA is a bidirectional pin used to transfer data into and
out of the device. It is an open drain output and may be
wire-ORed with any number of open drain or open col-
lector outputs.
An open drain output requires the use of a pull-up
resistor. For selecting typical values, refer to the Pull-
up resistor selection graph at the end of this data
sheet.
Device Select (S0, S1)
The device select inputs (S0, S1) are used to set bits in
the slave address. This allows up to four devices to
share a common bus. These inputs can be static or
actively driven. If used statically they must be tied to
VSS or VCC as appropriate. If actively driven, they must
be driven with CMOS levels (driven to VCC or VSS) and
they must be constant between each start and stop
issued on the SDA bus. These pins have an active pull
down internally and will be sensed as low if the pin is
left unconnected.
Write Protect (WP)
WP must be constant between each start and stop
issued on the SDA bus and is always active (not
gated). The WP pin has an active pull down to disable
the write protection when the input is left floating. The
Write Protect input controls the Hardware Write Protect
feature. When held LOW, Hardware Write Protection is
disabled. When this input is held HIGH, and the WPEN
bit in the Write Protect Register is set HIGH, the Write
Protect Register is protected, preventing changes to
the Block Lock Protection and WPEN bits.
PIN NAMES
Symbol
S0, S1
SDA
SCL
WP
VSS
VCC
NC
PIN CONFIGURATION
Description
Device Select Inputs
Serial Data
Serial Clock
Write Protect
Ground
Supply Voltage
No Connect
8-Lead XBGA: Top View
WP 1
VCC 2
SDA 3
SCL 4
8 S1
7 S0
6 VSS
5 S2
14-Lead TSSOP
S0 1
S1 2
14
13
NC 3
12
NC 4 X24257 11
NC 5
10
S2 6
9
VSS
7
8
VCC
WP
NC
NC
NC
SCL
SDA
8-Lead PDIP/SOIC
S0 1
8 VCC
S1
S2
27
3 X24257 6
WP
SCL
VSS 4
5 SDA
REV 1.1.1 10/15/00
www.xicor.com
Characteristics subject to change without notice. 2 of 19


Part Number X24257
Description 400kHz 2-Wire Serial EEPROM
Maker Xicor
Total Page 19 Pages
PDF Download

X24257 Datasheet PDF

View PDF for Mobile








Similar Datasheet

1 X24257 400kHz 2-Wire Serial EEPROM
Xicor





Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z

Site map

Webmaste! click here

Contact us

Buy Components

Privacy Policy