AT25DF321A-SH-T Atmel, AT25DF321A-SH-T Datasheet - Page 26

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

Specifications of AT25DF321A-SH-T

• 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
• Density: 32Mb
• Access Time (max): 5ns
• Interface Type: Serial (SPI)
• Address Bus: 1b
• Operating Supply Voltage (typ): 3.3V
• Operating Temp Range: -40C to 85C
• Package Type: SOIC
• Program/erase Volt (typ): 2.7 to 3.6V
• Sync/async: Synchronous
• Operating Temperature Classification: Industrial
• Operating Supply Voltage (min): 2.7V
• Operating Supply Voltage (max): 3.6V
• Word Size: 8b
• Number Of Words: 4M
• Supply Current: 19mA
• Mounting: Surface Mount
• Pin Count: 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10.2
26
Figure 10-1. Sector Lockdown
Freeze Sector Lockdown State
The current sector lockdown state can be permanently frozen so that no further modifications to the Sector Lockdown
Registers can be made; therefore, the Sector Lockdown command will be permanently disabled, and no additional sectors
can be locked down aside from those already locked down. Any attempts to issue the Sector Lockdown command after
the sector lockdown state has been frozen will be ignored.
Before the Freeze Sector Lockdown State command can be issued, the Write Enable command must have been
previously issued to set the WEL bit in the Status Register to a logical “1”. In addition, the Sector Lockdown Enabled
(SLE) bit in the Status Register must have also been previously set to the logical “1” state. To issue the Freeze Sector
Lockdown State command, the CS pin must first be asserted and the opcode of 34h must be clocked into the device
followed by three command specific address bytes of 55AA40h. After the three address bytes have been clocked in, a
confirmation byte of D0h must be clocked in immediately following the three address bytes. Any additional data clocked
into the device will be ignored. When the CS pin is deasserted, the current sector lockdown state will be permanently
frozen within a time of t
the SLE bit will be permanently reset to a logical “0” to indicate that the Sector Lockdown command is permanently
disabled.
The complete and correct three address bytes and the confirmation byte must be clocked into the device before the CS
pin is deasserted, and the CS pin must be deasserted on an even byte boundary (multiples of eight bits); otherwise, the
device will abort the operation. When the device aborts the Freeze Sector Lockdown State operation, the WEL bit in the
Status Register will be reset to a logical “0”; however, the state of the SLE bit will be unchanged.
Figure 10-2. Freeze Sector Lockdown State
SCK
SCK
Atmel AT25DF321A
SO
SO
CS
CS
SI
SI
MSB
HIGH-IMPEDANCE
MSB
HIGH-IMPEDANCE
0
0
0
0
0
0
1
1
1
LOCK
1
2
2
OPCODE
OPCODE
1
1
3
3
. In addition, the WEL bit in the Status Register will be reset back to the logical “0” state, and
0
0
4
4
0
1
5
5
1
0
6
6
1
0
7
7
MSB
MSB
A
0
ADDRESS BITS A23-A0
ADDRESS BITS A23-A0
8
8
A
1
9
9
A
0
A
0
29 30
29 30
A
0
A
0
31 32
31 32
MSB
MSB
CONFIRMATION BYTE IN
CONFIRMATION BYTE IN
1
1
1
1
33
33
0
0
34
34
1
1
35
35
0
0
36
36
0
0
37 38
37 38
0
0
0
0
39
39
3686D–DFLASH–12/09