2 Mbit / 4 Mbit SPI Serial Flash
SST25VF020 / SST25VF040
Data Sheet
Instructions
Instructions are used to Read, Write (Erase and Program),
and configure the SST25VF020/040. The instruction bus
cycles are 8 bits each for commands (Op Code), data, and
addresses. Prior to executing any Byte-Program, Auto
Address Increment (AAI) programming, Sector-Erase,
Block-Erase, or Chip-Erase instructions, the Write-Enable
(WREN) instruction must be executed first. The complete
list of the instructions is provided in Table 6. All instructions
are synchronized off a high to low transition of CE#. Inputs
will be accepted on the rising edge of SCK starting with the
most significant bit. CE# must be driven low before an
instruction is entered and must be driven high after the last
bit of the instruction has been shifted in (except for Read,
Read-ID and Read-Status-Register instructions). Any low
to high transition on CE#, before receiving the last bit of an
instruction bus cycle, will terminate the instruction in
progress and return the device to the standby mode.
Instruction commands (Op Code), addresses, and data are
all input from the most significant bit (MSB) first.
1
TABLE 6: DEVICE OPERATION INSTRUCTIONS
Bus Cycle2
1
2
3
4
5
Cycle Type/Operation3,4
SIN
SOUT
SIN
SOUT
SIN
SOUT
SIN
SOUT SIN SOUT
Read
03H
20H
52H
60H
02H
Hi-Z A23-A16 Hi-Z A15-A8 Hi-Z
Hi-Z A23-A16 Hi-Z A15-A8 Hi-Z
Hi-Z A23-A16 Hi-Z A15-A8 Hi-Z
A7-A0
Hi-Z
Hi-Z
Hi-Z
-
X
-
DOUT
Sector-Erase5,6
Block-Erase5,7
Chip-Erase6
Byte-Program6
Auto Address Increment (AAI) Program6,8 AFH
A7-A0
-
A7-A0
-
-
Hi-Z
-
-
-
-
-
-
-
Hi-Z A23-A16 Hi-Z A15-A8 Hi-Z
Hi-Z A23-A16 Hi-Z A15-A8 Hi-Z
A7-A0
Hi-Z DIN
Hi-Z DIN
Hi-Z
A7-A0
Hi-Z
Read-Status-Register (RDSR)
Enable-Write-Status-Register (EWSR)10
Write-Status-Register (WRSR)10
Write-Enable (WREN)
05H
50H
01H
06H
04H
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
X
DOUT
-
Note9
-
-
Note9
-
-
Note9
-
Data
-
-
Hi-Z
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-.
-
-
-
-
-
Write-Disable (WRDI)
-
-
-
-
12
Read-ID
90H or Hi-Z
ABH
00H
Hi-Z
00H
Hi-Z ID Addr11 Hi-Z
X
DOUT
T6.0 1231
1. AMS = Most Significant Address
AMS = A17 for SST25VF020 and A18 for SST25VF040
Address bits above the most significant bit of each density can be VIL or VIH
2. One bus cycle is eight clock periods.
3. Operation: SIN = Serial In, SOUT = Serial Out
4. X = Dummy Input Cycles (VIL or VIH); - = Non-Applicable Cycles (Cycles are not necessary)
5. Sector addresses: use AMS-A12, remaining addresses can be VIL or VIH
6. Prior to any Byte-Program, AAI-Program, Sector-Erase, Block-Erase, or Chip-Erase operation, the Write-Enable (WREN) instruction
must be executed.
7. Block addresses for: use AMS-A15, remaining addresses can be VIL or VIH
8. To continue programming to the next sequential address location, enter the 8-bit command, AFH,
followed by the data to be programmed.
9. The Read-Status-Register is continuous with ongoing clock cycles until terminated by a low to high transition on CE#.
10. The Enable-Write-Status-Register (EWSR) instruction and the Write-Status-Register (WRSR) instruction must work in conjunction of
each other. The WRSR instruction must be executed immediately (very next bus cycle) after the EWSR instruction to make both
instructions effective.
11. Manufacturer’s ID is read with A0=0, and Device ID is read with A0=1. All other address bits are 00H. The Manufacturer’s and Device
ID output stream is continuous until terminated by a low to high transition on CE#
12. Device ID = 43H for SST25VF020 and 44H for SST25VF040
©2004 Silicon Storage Technology, Inc.
S71231-04-000
6/04
8
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