AT25DF081A-MH-T Atmel, AT25DF081A-MH-T Datasheet - Page 27

• Manufacturer Part Number: AT25DF081A-MH-T
• Description: IC FLASH 8MBIT SPI 8UDFN
• Manufacturer: Atmel

Specifications of AT25DF081A-MH-T

• Format - Memory: FLASH
• Memory Type: DataFLASH
• Memory Size: 8M (4096 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-UDFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8715B–SFLSH–8/10
10.3
Read Sector Lockdown Registers
The Sector Lockdown Registers can be read to determine the current lockdown status of each physical 64-Kbyte
sector. To read the Sector Lockdown Register for a particular 64-Kbyte sector, the CS pin must first be asserted
and the opcode of 35h must be clocked in. Once the opcode has been clocked in, three address bytes designating
any address within the 64-Kbyte sector must be clocked in. After the address bytes have been clocked in, data will
be output on the SO pin during every subsequent clock cycle. The data being output will be a repeating byte of
either FFh or 00h to denote the value of the appropriate Sector Lockdown Register.
At clock frequencies above f
quencies above f
correct status of the appropriate Sector Lockdown Register.
Table 10-2.
Deasserting the CS pin will terminate the read operation and put the SO pin into a high-impedance state. The CS
pin can be deasserted at any time and does not require that a full byte of data be read.
Figure 10-3. Read Sector Lockdown Register
SCK
Output Data
SO
CS
SI
FFh
00h
Read Sector Lockdown Register – Output Data
HIGH-IMPEDANCE
MSB
0
CLK
Sector Lockdown Register Value
Sector Lockdown Register value is 1 (sector is permanently locked down)
0
Sector Lockdown Register value is 0 (sector is not locked down)
0
1
, at least two bytes of data must be clocked out from the device in order to determine the
1
2
OPCODE
1
3
0
4
CLK
1
5
, the first byte of data output will not be valid. Therefore, if operating at clock fre-
0
6
1
7
MSB
A
8
A
9
ADDRESS BITS A23-A0
A
10 11
A
A
12
A
A
29 30
A
A
31 32
MSB
X
X
33
DON'T CARE
X
34
X
35
X
36
Atmel AT25DF081A
X
37 38
X
X
39
MSB
D
40
D
41
DATA BYTE
D
42 43
D
D
44
D
45
D
46
D
47 48
MSB
D
D
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