24AA52-I/MS Microchip Technology, 24AA52-I/MS Datasheet - Page 9

• Manufacturer Part Number: 24AA52-I/MS
• Description: IC EEPROM 2KBIT 400KHZ 8MSOP
• Manufacturer: Microchip Technology

Specifications of 24AA52-I/MS

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 2K (256 x 8)
• Speed: 100kHz, 400kHz
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 1.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 24AA52I/MS

6.0
The 24XXX52 has a software write-protect feature that
allows the lower half of the array (addresses 00h-7Fh)
to be permanently write-protected, as well as a WP pin
that can be used to protect the entire array.
6.1
The software write-protect feature is invoked by writing
to the write-protect register. This is done by sending a
command similar to a normal Write command. As shown
in Figure 6-1, the write-protect register is written by
sending a Write command with the slave address set to
‘0110’ instead of ‘1010’ and the address bits and data
bits are “don’t cares.” Once the software write-protect
register has been written, the device will not
acknowledge the ‘0110’ control byte.
FIGURE 6-1:
6.2
It is possible to reset the software write-protect feature
on the 24XXX52. This is done by sending a command
similar to setting the software write-protect command,
except the command is sent before the regular control
byte and is ‘1001’ . The full command will be shown in
Figure 6-2. In order for the command to work, a voltage
of Vcc + 5.5V must be applied to the WP pin and must
be sustained for 1 S before the command is given. The
customer should also allow for a 5 ms delay after the
Stop bit for T
© 2005 Microchip Technology Inc.
SDA Line
Bus Activity
Master
Bus Activity
WRITE PROTECTION
Software Write-Protect
Resetting the Software
Write-Protect Fuse
WC
.
S
T
A
R
T
S
SETTING WRITE-PROTECT REGISTER
0
1
1
Control
Byte
0
A
C
K
Address
Word
24AA52/24LCS52
A
C
K
Data
DS21166J-page 9
A
C
K
P
S
T
O
P