25AA256-I/SM Microchip Technology, 25AA256-I/SM Datasheet - Page 9

• Manufacturer Part Number: 25AA256-I/SM
• Description: IC EEPROM 256KBIT 10MHZ 8SOIC
• Manufacturer: Microchip Technology

Specifications of 25AA256-I/SM

• Memory Size: 256K (32K x 8)
• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Speed: 10MHz
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 1.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOIC (5.3mm Width), 8-SOP, 8-SOEIAJ
• Memory Configuration: 32K X 8
• Ic Interface Type: Serial, SPI
• Clock Frequency: 10MHz
• Access Time: 50ns
• Supply Voltage Range: 1.8V To 5.5V
• Memory Case Style: SOIC
• No. Of Pins: 8
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2.4
The 25XX256 contains a write enable latch.
Table 2-1 for the Write-Protect Functionality Matrix.
This latch must be set before any write operation will be
completed internally. The WREN instruction will set the
latch, and the WRDI will reset the latch.
FIGURE 2-4:
FIGURE 2-5:
© 2007 Microchip Technology Inc.
Write Enable (WREN) and Write
Disable (WRDI)
WRITE ENABLE SEQUENCE (WREN)
WRITE DISABLE SEQUENCE (WRDI)
SCK
SO
CS
SI
SCK
SO
CS
SI
0
0
0
0
0
1
0
1
See
High-Impedance
0
High-Impedance
0
2
2
0
0
3
3
The following is a list of conditions under which the
write enable latch will be reset:
• Power-up
• WRDI instruction successfully executed
• WRSR instruction successfully executed
• WRITE instruction successfully executed
0
0
4
4
25AA256/25LC256
1
5
1
5
1
6
1 0
6
0
7
0
7
DS21822F-page 9