Datasheet

©2011 Silicon Storage Technology, Inc. DS25078A 11/11
15
2 Mbit SPI Serial Flash
SST25VF020
Not Recommended for New Designs
A
Microchip Technology Company
Write-Enable (WREN)
The Write-Enable (WREN) instruction sets the Write-Enable-Latch bit to 1 allowing Write operations to
occur. The WREN instruction must be executed prior to any Write (Program/Erase) operation. CE#
must be driven high before the WREN instruction is executed.
Figure 12:Write Enable (WREN) Sequence
Write-Disable (WRDI)
The Write-Disable (WRDI) instruction resets the Write-Enable-Latch bit and AAI bit to 0 disabling any
new Write operations from occurring. CE# must be driven high before the WRDI instruction is exe-
cuted.
Figure 13:Write Disable (WRDI) Sequence
Enable-Write-Status-Register (EWSR)
The Enable-Write-Status-Register (EWSR) instruction arms the Write-Status-Register (WRSR)
instruction and opens the status register for alteration. The Enable-Write-Status-Register instruction
does not have any effect and will be wasted, if it is not followed immediately by the Write-Status-Regis-
ter (WRSR) instruction. CE# must be driven low before the EWSR instruction is entered and must be
driven high before the EWSR instruction is executed.
CE#
SO
SI
SCK
01234567
06
HIGH IMPEDANCE
MODE 0
MODE 3
1231 F11.1
MSB
CE#
SO
SI
SCK
01234567
04
HIGH IMPEDANCE
MODE 0
MODE 3
1231 F12.1
MSB