AT25DF321A-SH-B Atmel, AT25DF321A-SH-B Datasheet - Page 22

• Manufacturer Part Number: AT25DF321A-SH-B
• Description: IC FLASH 32MBIT 100MHZ 8SOIC
• Manufacturer: Atmel

Specifications of AT25DF321A-SH-B

• Format - Memory: FLASH
• Memory Type: DataFLASH
• Memory Size: 32M (16384 pages x 256 Bytes)
• Speed: 100MHz
• Interface: SPI, RapidS
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOIC (5.3mm Width), 8-SOP, 8-SOEIAJ
• Memory Configuration: 16384 Pages X 256 Bytes
• Interface Type: Serial, SPI
• Clock Frequency: 100MHz
• Supply Voltage Range: 2.7V To 3.6V
• Memory Case Style: SOIC
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

22
Table 9-2.
Essentially, if the SPRL bit of the Status Register is in the logical “0” state (Sector Protection Registers are not locked),
then writing a 00h to the first byte of the Status Register will perform a Global Unprotect without changing the state of the
SPRL bit. Similarly, writing a 7Fh to the first byte of the Status Register will perform a Global Protect and keep the SPRL bit
in the logical “0” state. The SPRL bit can, of course, be changed to a logical “1” by writing an FFh if software-locking or
hardware-locking is desired along with the Global Protect.
Atmel AT25DF321A
State
WP
0
0
1
1
Current
SPRL
Value
Valid SPRL and Global Protect/Unprotect Conditions
0
1
0
1
New Write Status
Register Byte 1
7 6 5 4 3 2 1 0
0 x 0 0 0 0 x x
0 x 0 0 0 1 x x
0 x 1 1 1 0 x x
0 x 1 1 1 1 x x
1 x 0 0 0 0 x x
1 x 0 0 0 1 x x
1 x 1 1 1 0 x x
1 x 1 1 1 1 x x
0 x 0 0 0 0 x x
0 x 0 0 0 1 x x
0 x 1 1 1 0 x x
0 x 1 1 1 1 x x
1 x 0 0 0 0 x x
1 x 0 0 0 1 x x
1 x 1 1 1 0 x x
1 x 1 1 1 1 x x
0 x 0 0 0 0 x x
0 x 0 0 0 1 x x
0 x 1 1 1 0 x x
0 x 1 1 1 1 x x
1 x 0 0 0 0 x x
1 x 0 0 0 1 x x
1 x 1 1 1 0 x x
1 x 1 1 1 1 x x
x x x x x x x x
Data
Bit
↕
↕
↕
↕
↕
↕
Protection Operation
Global Unprotect – all Sector Protection Registers reset to 0
No change to current protection
No change to current protection
No change to current protection
Global Protect – all Sector Protection Registers set to 1
Global Unprotect – all Sector Protection Registers reset to 0
No change to current protection
No change to current protection
No change to current protection
Global Protect – all Sector Protection Registers set to 1
No change to the current protection level. All sectors currently protected will remain
protected and all sectors currently unprotected will remain unprotected
The Sector Protection Registers are hard-locked and cannot be changed when the WP pin
is LOW and the current state of SPRL is 1. Therefore, a Global Protect/Unprotect will not
occur. In addition, the SPRL bit cannot be changed (the WP pin must be HIGH in order to
change SPRL back to a 0)
Global Unprotect – all Sector Protection Registers reset to 0
No change to current protection
No change to current protection
No change to current protection
Global Protect – all Sector Protection Registers set to 1
Global Unprotect – all Sector Protection Registers reset to 0
No change to current protection
No change to current protection
No change to current protection
Global Protect – all Sector Protection Registers set to 1
No change to the current protection level. All sectors currently protected will
remain protected, and all sectors currently unprotected will remain unprotected
The Sector Protection Registers are soft-locked and cannot be changed when
the current state of SPRL is one. Therefore, a Global Protect/Unprotect will not
occur. However, the SPRL bit can be changed back to a zero from a one since the
WP pin is HIGH. To perform a Global Protect/Unprotect, the Write Status
Register command must be issued again after the SPRL bit has been changed
from a one to a zero.
3686D–DFLASH–12/09
SPRL
Value
New
0
0
0
0
0
1
1
1
1
1
0
0
0
0
0
1
1
1
1
1
0
0
0
0
0
1
1
1
1
1