8

Data Sheet

4 Mbit SPI Serial Flash

SST25VF040B

©2006 Silicon Storage Technology, Inc.

S71295-01-000

1/06

Instructions

Instructions are used to read, write (Erase and Program),

and configure the SST25VF040B. 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, Write-Status-Register, or Chip-Erase instruc-

tions, the Write-Enable (WREN) instruction must be exe-

cuted first. The complete list of instructions is provided in

Table 5. 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 standby mode. Instruction commands (Op Code),

addresses, and data are all input from the most significant

bit (MSB) first.

TABLE

Instruction

Description

1. One bus cycle is eight clock periods.

Address

Dummy

Cycle(s)

Data

Cycle(s)

Maximum

Frequency

Read

Read Memory at 25 MHz

0000 0011b (03H)

3

0

1 to

∞

25 MHz

High-Speed Read

Read Memory at 50 MHz

0000 1011b (0BH)

3

1

1 to

∞

50 MHz

Erase 4 KByte of

memory array

0010 0000b (20H)

3

0

0

50 MHz

Erase 32 KByte block

of memory array

0101 0010b (52H)

3

0

0

50 MHz

Erase 64 KByte block

of memory array

1101 1000b (D8H)

3

0

0

50 MHz

Chip-Erase

Erase Full Memory Array

0110 0000b (60H) or

1100 0111b (C7H)

00

0

50 MHz

Byte-Program

To Program One Data Byte

0000 0010b (02H)

3

0

1

50 MHz

6. To continue programming to the next sequential address location, enter the 8-bit command, ADH, followed by 2 bytes of data to be

Auto Address Increment

Programming

1010 1101b (ADH)

3

0

2 to

∞

50 MHz

7. The Read-Status-Register is continuous with ongoing clock cycles until terminated by a low to high transition on CE#.

Read-Status-Register

0000 0101b (05H)

0

0

1 to

∞

50 MHz

EWSR

Enable-Write-Status-Register

0101b 0000b (50H)

0

0

0

50 MHz

WRSR

Write-Status-Register

0000 0001b (01H)

0

0

1

50 MHz

WREN

Write-Enable

0000 0110b (06H)

0

0

0

50 MHz

WRDI

Write-Disable

0000 0100b (04H)

0

0

0

50 MHz

device ID output stream is continuous until terminated by a low-to-high transition on CE#.

Read-ID

1001 0000b (90H) or

1010 1011b (ABH)

30

1 to

∞

50 MHz

JEDEC-ID

JEDEC ID read

1001 1111b (9FH)

0

0

3 to

∞

50 MHz

EBSY

Enable SO to output RY/BY#

status during AAI programming

0111 0000b (70H)

0

0

0

50 MHz

DBSY

Disable SO to output RY/BY#

status during AAI programming

1000 0000b (80H)

0

0

0

50 MHz

T5.0

1295