4 Mbit SPI Serial Flash
SST25VF040B
Data Sheet
JEDEC Read-ID
The JEDEC Read-ID instruction identifies the device as
SST25VF040B and the manufacturer as SST. The device
information can be read from executing the 8-bit command,
9FH. Following the JEDEC Read-ID instruction, the 8-bit
manufacturer’s ID, BFH, is output from the device. After
that, a 16-bit device ID is shifted out on the SO pin. Byte 1,
BFH, identifies the manufacturer as SST. Byte 2, 25H, iden-
tifies the memory type as SPI Serial Flash. Byte 3, 8DH,
identifies the device as SST25VF040B. The instruction
sequence is shown in Figure 20. The JEDEC Read ID
instruction is terminated by a low to high transition on CE#
at any time during data output.
CE#
MODE 3
MODE 0
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
SCK
9F
SI
HIGH IMPEDANCE
BF
25
8D
SO
MSB
MSB
1295 JEDECID.1
FIGURE 20: JEDEC Read-ID Sequence
TABLE 6: JEDEC Read-ID Data
Manufacturer’s ID
Device ID
Memory Type Memory Capacity
Byte1
BFH
Byte 2
25H
Byte 3
8DH
T6.0 1295
©2009 Silicon Storage Technology, Inc.
S71295-05-000
10/09
20
SST [ SILICON STORAGE TECHNOLOGY, INC ]
