X24257 Datasheet, PDF (2/19 Pages) Xicor Inc. – 400kHz 2-Wire Serial EEPROM with Block Lock

X24257 – Preliminary Information
PIN DESCRIPTIONS
PIN NAMES
Serial Clock (SCL)
Symbol
Description
The SCL input is used to clock all data into and out of
the device.
Serial Data (SDA)
t _{SDA is a bidirectional pin used to transfer data into and}
out of the device. It is an open drain output and may be
c wire-ORed with any number of open drain or open col-
lector outputs.
u ^{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
d sheet.
Device Select (S₀, S₁)
o _{The device select inputs (S0, S1) are used to set bits in}
r ^{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
P ^{VSS or VCC as appropriate. If actively driven, they must}
be driven with CMOS levels (driven to V_CC or V_SS) and
they must be constant between each start and stop
issued on the SDA bus. These pins have an active pull
e ^{down internally and will be sensed as low if the pin is}
left unconnected.
t _{Write Protect (WP)}
WP must be constant between each start and stop
e _{issued on the SDA bus and is always active (not}
l ^{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
o _{feature. When held LOW, Hardware Write Protection is}
disabled. When this input is held HIGH, and the WPEN
s ^{bit in the Write Protect Register is set HIGH, the Write}
Protect Register is protected, preventing changes to
Ob ^{the Block Lock Protection and WPEN bits.}
S₀, S₁
SDA
SCL
WP
V_SS
V_CC
NC
PIN CONFIGURATION
Device Select Inputs
Serial Data
Serial Clock
Write Protect
Ground
Supply Voltage
No Connect
8-Lead XBGA: Top View
WP ¹
V_CC 2
SDA 3
SCL 4
8 S₁
7 S₀
6 ^VSS
5 S₂
14-Lead TSSOP
S₀
1
14
S₁
2
13
NC ₃
12
NC
4 _X24257 11
NC 5
10
S₂
6
9
V_SS
7
8
V_CC
WP
NC
NC
NC
SCL
SDA
8-Lead PDIP/SOIC
S₀ 1
8
V_CC
S₁
S₂
2
7
3 ^{X24257 6}
WP
SCL
V_{SS 4}
5 _SDA
REV 1.1.1 10/15/00
www.xicor.com
Characteristics subject to change without notice. 2 of 19