25AA1024 Microchip Technology, 25AA1024 Datasheet - Page 15

• Manufacturer Part Number: 25AA1024
• Description: 1 Mbit SPI Bus Serial EEPROM
• Manufacturer: Microchip Technology

2.9
The Sector Erase function will erase all bits (FFh)
inside the given sector. A Write Enable (WREN) instruc-
tion must be given prior to attempting a Sector Erase.
This is done by setting CS low and then clocking out
the proper instruction into the 25XX1024. After all
eight bits of the instruction are transmitted, the CS
must be brought high to set the write enable latch.
The Sector Erase function is entered by driving CS
low, followed by the instruction code (Figure 2-9), and
three address bytes. Any address inside the sector to
be erased is a valid address.
FIGURE 2-9:
© 2007 Microchip Technology Inc.
SECTOR ERASE
SCK
CS
SO
SI
SECTOR ERASE SEQUENCE
1
0
1
1
0
Instruction
2
1
3
1
4
0
5
High-Impedance
Preliminary
0
6
0
7
23 22 21 20
8
CS must then be driven high after the last bit if the
address or the Sector Erase will not execute. Once the
CS is driven high, the self-timed Sector Erase cycle is
started. The WIP bit in the STATUS register can be
read to determine when the Sector Erase cycle is
complete.
If a SECTOR ERASE instruction is given to an address
that has been protected by the Block Protect bits (BP0,
BP1) then the sequence will be aborted and no erase
will occur.
See Table 2-3 for Sector Addressing.
9 10 11
25AA1024/25LC1024
24-bit Address
29 30 31
2
1
0
DS21836D-page 15