AT25DF161-MH-Y Atmel, AT25DF161-MH-Y Datasheet - Page 22

• Manufacturer Part Number: AT25DF161-MH-Y
• Description: IC FLASH 16MBIT 100MHZ 8UDFN
• Manufacturer: Atmel

Specifications of AT25DF161-MH-Y

• Format - Memory: FLASH
• Memory Type: DataFLASH
• Memory Size: 16M (2M x 8)
• Speed: 100MHz
• Interface: SPI, RapidS
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-UDFN
• 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.
If the desire is to only change the SPRL bit without performing a Global Protect or Global Unprotect, then the system can
simply write a 0Fh to the first byte of the Status Register to change the SPRL bit from a logical “1” to a logical “0”
provided the WP pin is deasserted. Likewise, the system can write an F0h to change the SPRL bit from a logical “0” to a
Atmel AT25DF161
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 1. Therefore, a Global Protect/Unprotect will not occur. However, the
SPRL bit can be changed back to a 0 from a 1 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 1 to a 0.
3687E–DFLASH–11/10
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