AT25DF641-S3H-T Atmel, AT25DF641-S3H-T Datasheet - Page 29

• Manufacturer Part Number: AT25DF641-S3H-T
• Description: IC FLASH 64MBIT 100MHZ 16SOIC
• Manufacturer: Atmel

Specifications of AT25DF641-S3H-T

• Format - Memory: FLASH
• Memory Type: DataFLASH
• Memory Size: 64M (32K pages x 256 bytes)
• Speed: 100MHz
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-SOIC (0.300", 7.5mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3680F–DFLASH–4/10
Before the Sector Lockdown 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 by using the Write Status
Register Byte 2 command (see “Write Status Register Byte 2” on page 39). To issue the Sector Lockdown
command, the
three address bytes designating any address within the 64-Kbyte sector to be locked down. After the three
address bytes have been clocked in, a confirmation byte of D0h must also be clocked in immediately following the
three address bytes. Any additional data clocked into the device after the first byte of data will be ignored. When
the
set to the logical “1” state, and the sector itself will then be permanently locked down from program and erase
operations within a time of t
state.
The complete three address bytes and the correct confirmation byte value of D0h must be clocked into the device
before the
bits); otherwise, the device will abort the operation. When the device aborts the Sector Lockdown operation, the
state of the corresponding Sector Lockdown Register as well as the SLE bit in the Status Register will be
unchanged; however, the WEL bit in the Status Register will be reset to a logical “0”.
As a safeguard against accidental or erroneous locking down of sectors, the Sector Lockdown command can be
enabled and disabled as needed by using the SLE bit in the Status Register. In addition, the current sector
lockdown state can be frozen so that no further modifications to the Sector Lockdown Registers can be made
(see “Freeze Sector Lockdown State”). If the Sector Lockdown command is disabled or if the sector lockdown
state is frozen, then any attempts to issue the Sector Lockdown command will be ignored, and the device will
reset the WEL bit in the Status Register back to a logical “0” and return to the idle state once the
deasserted.
Figure 9-1.
SCK
SO
CS
CS
SI
pin is deasserted, the Sector Lockdown Register corresponding to the sector addressed by A23-A0 will be
CS
Sector Lockdown
pin is deasserted, and the
CS
pin must first be asserted and the opcode of 33h must be clocked into the device followed by
MS B
HIG H-IMP E DANC E
0
0
0
1
1
2
OP C ODE
LOCK
1
3
0
. In addition, the WEL bit in the Status Register will be reset back to the logical “0”
4
0
5
1
6
1
7
MS B
A
CS
ADDR E S S B IT S A23-A0
8
A
9
pin must be deasserted on an even byte boundary (multiples of eight
A
A
29 30
A
A
31 32
MS B
C ONF IR MAT ION B Y T E IN
1
1
33
0
34
1
35
0
36
0
37 38
0
0
39
Atmel AT25DF641
CS
pin has been
29