25LC040A-E/ST Microchip Technology, 25LC040A-E/ST Datasheet - Page 9
![IC EEPROM 4KBIT 10MHZ 8TSSOP](/photos/6/59/65937/c04-086_st_sml.jpg)
25LC040A-E/ST
Manufacturer Part Number
25LC040A-E/ST
Description
IC EEPROM 4KBIT 10MHZ 8TSSOP
Manufacturer
Microchip Technology
Specifications of 25LC040A-E/ST
Format - Memory
EEPROMs - Serial
Memory Type
EEPROM
Memory Size
4K (512 x 8)
Speed
10MHz
Interface
SPI, 3-Wire Serial
Voltage - Supply
2.5 V ~ 5.5 V
Operating Temperature
-40°C ~ 125°C
Package / Case
8-TSSOP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
2.4
The 25XX040A contains a write enable latch.
Table 2-4 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:
© 2009 Microchip Technology Inc.
Write Enable (WREN) and Write
Disable (WRDI)
WRITE ENABLE SEQUENCE (WREN)
WRITE DISABLE SEQUENCE (WRDI)
SCK
CS
SO
SCK
SI
CS
SO
SI
0
0
0
0
0
1
0
1
See
High-impedance
0
High-impedance
0
2
2
0
0
3
3
25AA040A/25LC040A
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
• WP pin is brought low
0
0
4
4
1
5
1
5
1
6
1 0
6
0
7
0
7
DS21827F-page 9