SST25LF020A-33-4I-QAE - Microchip Technology, Inc.

Microchip Technology Company

Not Recommended for New Designs

www.microchip.com

Features

• Single 3.0-3.6V Read and Write Operations

• Serial Interface Architecture

– SPI Compatible: Mode 0 and Mode 3

• 33 MHz Max Clock Frequency

• Superior Reliability

– Endurance: 100,000 Cycles (typical)

– Greater than 100 years Data Retention

• Low Power Consumption:

– Active Read Current: 7 mA (typical)

– Standby Current: 8 µA (typical)

• Flexible Erase Capability

– Uniform 4 KByte sectors

– Uniform 32 KByte overlay blocks

• Fast Erase and Byte-Program:

– Chip-Erase Time: 70 ms (typical)

– Sector- or Block-Erase Time: 18 ms (typical)

– Byte-Program Time: 14 µs (typical)

• Auto Address Increment (AAI) Programming

– Decrease total chip programming time over Byte-Pro-

gram operations

• End-of-Write Detection

– Software Status

• Hold Pin (HOLD#)

– Suspends a serial sequence to the memory

without deselecting the device

• Write Protection (WP#)

– Enables/Disables the Lock-Down function of the status

• Software Write Protection

– Write protection through Block-Protection bits in status

• Temperature Range

– Commercial: 0°C to +70°C

– Industrial: -40°C to +85°C

– Extended: -20°C to +85°C

• Packages Available

– 8-lead SOIC 150 mil body width

for SST25LF020A

– 8-contact WSON (5mm x 6mm)

• All non-Pb (lead-free) devices are RoHS compliant

2 Mbit SPI Serial Flash

SST25LF020A

SST serial flash family features a four-wire, SPI-compatible interface that allows

for a low pin-count package occupying less board space and ultimately lowering

total system costs. SST25LF020A SPI serial flash memory is manufactured with

SST proprietary, high performance CMOS SuperFlash Technology. The split-gate

cell design and thick-oxide tunneling injector attain better reliability and manufac-

turability compared with alternate approaches.

Not recommended for new designs.

Please use SST25VF020B

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Product Description

SST’s serial flash family features a four-wire, SPI-compatible interface that allows for a low pin-

count package occupying less board space and ultimately lowering total system costs.

SST25LF020A SPI serial flash memories are manufactured with SST’s proprietary, high perfor-

mance CMOS SuperFlash technology. The split-gate cell design and thick-oxide tunneling injector

attain better reliability and manufacturability compared with alternate approaches.

The SST25LF020A devices significantly improve performance, while lowering power consumption.

The total energy consumed is a function of the applied voltage, current, and time of application.

Since for any given voltage range, the SuperFlash technology uses less current to program and

has a shorter erase time, the total energy consumed during any Erase or Program operation is

less than alternative flash memory technologies. The SST25LF020A devices operate with a single

3.0-3.6V power supply.

The SST25LF020A devices are offered in an 8-lead SOIC 150 mil body width (SA) package, and in

an 8-contact WSON package. See Figure 2 for the pin assignments.

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Block Diagram

Figure 1: Functional Block Diagram

1242 B1.0

I/O Buffers

and

Data Latches

SuperFlash

Memory

X - Decoder

Control Logic

Address

Buffers

and

Latches

CE#

Y - Decoder

SCK SI SO WP# HOLD#

Serial Interface

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Pin Description

Figure 2: Pin Assignments

Table 1: Pin Description

Symbol Pin Name Functions

SCK Serial Clock To provide the timing of the serial interface.

Commands, addresses, or input data are latched on the rising edge of the clock input,

while output data is shifted out on the falling edge of the clock input.

SI Serial Data

Input

To transfer commands, addresses, or data serially into the device.

Inputs are latched on the rising edge of the serial clock.

SO Serial Data

Output

To transfer data serially out of the device.

Data is shifted out on the falling edge of the serial clock.

CE# Chip Enable The device is enabled by a high to low transition on CE#. CE# must remain low for the

duration of any command sequence.

WP# Write Protect The Write Protect (WP#) pin is used to enable/disable BPL bit in the status register.

HOLD# Hold To temporarily stop serial communication with SPI flash memory without resetting the

device.

VDD Power Supply To provide power supply (3.0-3.6V).

VSS Ground

T1.0 25080

8-lead SOIC 8-contact WSON

CE#

WP#

VSS

Top View

VDD

HOLD#

SCK

1242 08-wson P2.0

CE#

WP#

VSS

VDD

HOLD#

SCK

Top View

1242 08-soic P1.0

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Memory Organization

The SST25LF020A SuperFlash memory array is organized in 4 KByte sectors with 32 KByte overlay

blocks.

Device Operation

The SST25LF020A is accessed through the SPI (Serial Peripheral Interface) bus compatible protocol.

The SPI bus consist of four control lines; Chip Enable (CE#) is used to select the device, and data is

accessed through the Serial Data Input (SI), Serial Data Output (SO), and Serial Clock (SCK).

The SST25LF020A supports both Mode 0 (0,0) and Mode 3 (1,1) of SPI bus operations. The differ-

ence between the two modes, as shown in Figure 3, is the state of the SCK signal when the bus mas-

ter is in Stand-by mode and no data is being transferred. The SCK signal is low for Mode 0 and SCK

signal is high for Mode 3. For both modes, the Serial Data In (SI) is sampled at the rising edge of the

SCK clock signal and the Serial Data Output (SO) is driven after the falling edge of the SCK clock sig-

nal.

Figure 3: SPI Protocol

1242 F02.0

MODE 3

SCK

CE#

MODE 3

DON T CARE

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1

Bit 0

MODE 0MODE 0

HIGH IMPEDANCE

MSB

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Hold Operation

HOLD# pin is used to pause a serial sequence underway with the SPI flash memory without resetting

the clocking sequence. To activate the HOLD# mode, CE# must be in active low state. The HOLD#

mode begins when the SCK active low state coincides with the falling edge of the HOLD# signal. The

HOLD mode ends when the HOLD# signal’s rising edge coincides with the SCK active low state.

If the falling edge of the HOLD# signal does not coincide with the SCK active low state, then the device

enters Hold mode when the SCK next reaches the active low state. Similarly, if the rising edge of the

HOLD# signal does not coincide with the SCK active low state, then the device exits in Hold mode

when the SCK next reaches the active low state. See Figure 4 for Hold Condition waveform.

Once the device enters Hold mode, SO will be in high-impedance state while SI and SCK can be VIL or

VIH.

If CE# is driven active high during a Hold condition, it resets the internal logic of the device. As long as

HOLD# signal is low, the memory remains in the Hold condition. To resume communication with the

device, HOLD# must be driven active high, and CE# must be driven active low. See Figure 19 for Hold

timing.

Figure 4: Hold Condition Waveform

Write Protection

SST25LF020A provides software Write protection. The Write Protect pin (WP#) enables or disables

the lock-down function of the status register. The Block-Protection bits (BP1, BP0, and BPL) in the sta-

tus register provide Write protection to the memory array and the status register. See Table 4 for Block-

Protection description.

Active Hold Active Hold Active

1242 F03.0

SCK

HOLD#

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Write Protect Pin (WP#)

The Write Protect (WP#) pin enables the lock-down function of the BPL bit (bit 7) in the status register.

When WP# is driven low, the execution of the Write-Status-Register (WRSR) instruction is determined

by the value of the BPL bit (see Table 2). When WP# is high, the lock-down function of the BPL bit is

disabled.

Status Register

The software status register provides status on whether the flash memory array is available for any

Read or Write operation, whether the device is Write enabled, and the state of the memory Write pro-

tection. During an internal Erase or Program operation, the status register may be read only to deter-

mine the completion of an operation in progress. Table 3 describes the function of each bit in the

software status register.

Busy

The Busy bit determines whether there is an internal Erase or Program operation in progress. A “1” for

the Busy bit indicates the device is busy with an operation in progress. A “0” indicates the device is

ready for the next valid operation.

Table 2: Conditions to execute Write-Status-Register (WRSR) Instruction

WP# BPL Execute WRSR Instruction

L 1 Not Allowed

L 0 Allowed

H X Allowed

T2.0 25080

Table 3: Software Status Register

Bit Name Function

Default at

Power-up Read/Write

0 BUSY 1 = Internal Write operation is in progress

0 = No internal Write operation is in progress

1 WEL 1 = Device is memory Write enabled

0 = Device is not memory Write enabled

2 BP0 Indicate current level of block write protection (See

Table 4)

1 R/W

3 BP1 Indicate current level of block write protection (See

Table 4)

1 R/W

4:5 RES Reserved for future use 0 N/A

6 AAI Auto Address Increment Programming status

1 = AAI programming mode

0 = Byte-Program mode

7 BPL 1 = BP1, BP0 are read-only bits

0 = BP1, BP0 are read/writable

0 R/W

T3.0 25080

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Write Enable Latch (WEL)

The Write-Enable-Latch bit indicates the status of the internal memory Write Enable Latch. If the

Write-Enable-Latch bit is set to “1”, it indicates the device is Write enabled. If the bit is set to “0” (reset),

it indicates the device is not Write enabled and does not accept any memory Write (Program/Erase)

commands. The Write-Enable-Latch bit is automatically reset under the following conditions:

•Power-up

•Write-Disable (WRDI) instruction completion

•Byte-Program instruction completion

•Auto Address Increment (AAI) programming reached its highest memory address

•Sector-Erase instruction completion

•Block-Erase instruction completion

•Chip-Erase instruction completion

Block Protection (BP1, BP0)

The Block-Protection (BP1, BP0) bits define the size of the memory area, as defined in Table 4, to be

software protected against any memory Write (Program or Erase) operations. The Write-Status-Regis-

ter (WRSR) instruction is used to program the BP1 and BP0 bits as long as WP# is high or the Block-

Protect-Lock (BPL) bit is 0. Chip-Erase can only be executed if Block-Protection bits are both 0. After

power-up, BP1 and BP0 are set to 1.

Block Protection Lock-Down (BPL)

WP# pin driven low (VIL), enables the Block-Protection-Lock-Down (BPL) bit. When BPL is set to 1, it

prevents any further alteration of the BPL, BP1, and BP0 bits. When the WP# pin is driven high (VIH),

the BPL bit has no effect and its value is “Don’t Care”. After power-up, the BPL bit is reset to 0.

Auto Address Increment (AAI)

The Auto Address Increment Programming-Status bit provides status on whether the device is in AAI

programming mode or Byte-Program mode. The default at power up is Byte-Program mode.

Table 4: Software Status Register Block Protection1

1. Default at power-up for BP1 and BP0 is ‘11’.

Protection Level

Status Register Bit Protected Memory Area

BP1 BP0 2 Mbit

0 0 0 None

1 (1/4 Memory Array) 0 1 030000H-03FFFFH

2 (1/2 Memory Array) 1 0 020000H-03FFFFH

3 (Full Memory Array) 1 1 000000H-03FFFFH

T4.0 25080

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Instructions

Instructions are used to Read, Write (Erase and Program), and configure the SST25LF020A. The

instruction bus cycles are 8 bits each for commands (Op Code), data, and addresses. Prior to execut-

ing 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 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 the standby mode. Instruction commands (Op Code), addresses,

and data are all input from the most significant bit (MSB) first.

Table 5: Device Operation Instructions1

1. AMS = Most Significant Address

AMS =A

17 for SST25LF020A

Address bits above the most significant bit of each density can be VIL or VIH

Cycle Type/

Operation2,3

2. Operation: SIN = Serial In, SOUT = Serial Out

3. X = Dummy Input Cycles (VIL or VIH); - = Non-Applicable Cycles (Cycles are not necessary)

Max

Freq

MHz

Bus Cycle4

4. One bus cycle is eight clock periods.

123456

SIN SOUT SIN SOUT SIN SOUT SIN SOUT SIN SOUT SIN SOUT

Read 20 03H Hi-Z A23-

A16

Hi-Z A15-

Hi-Z A7-A0Hi-Z X DOUT

High-Speed-Read

0BH Hi-Z A23-

A16

Hi-Z A15-

Hi-Z A7-A0Hi-Z X X X DOUT

Sector-Erase5,6

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.

20H Hi-Z A23-

A16

Hi-Z A15-

Hi-Z A7-A0Hi-Z - -

Block-Erase5,7 52H Hi-Z A23-

A16

Hi-Z A15-

Hi-Z A7-A0Hi-Z - -

Chip-Erase660H Hi-Z - - ------

Byte-Program602H Hi-Z A23-

A16

Hi-Z A15-

Hi-Z A7-A0Hi-Z DIN Hi-Z

Auto Address Increment

(AAI) Single-Byte

Program6,8

AFH Hi-Z A23-

A16

Hi-Z A15-

Hi-Z A7-A0Hi-Z DIN Hi-Z

Read-Status-Register

(RDSR)

05H Hi-Z X DOUT - Note

- Note

- Note9

Enable-Write-Status-

(EWSR)10

50H Hi-Z - - ------

Write-Status-Register

(WRSR)10

01H Hi-Z Data Hi-Z - - -. - - -

Write-Enable (WREN) 06H Hi-Z - - ------

Write-Disable (WRDI) 04H Hi-Z - - ------

Read-ID 90H

ABH

Hi-Z 00H Hi-Z 00H Hi-Z ID

Addr

Hi-Z X DOUT

T5.0 25080

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Read (20 MHz)

The Read instruction supports up to 20 MHz, it outputs the data starting from the specified address

location. The data output stream is continuous through all addresses until terminated by a low to high

transition on CE#. The internal address pointer will automatically increment until the highest memory

address is reached. Once the highest memory address is reached, the address pointer will automati-

cally increment to the beginning (wrap-around) of the address space, i.e. for 2 Mbit density, once the

data from address location 3FFFFH had been read, the next output will be from address location

00000H.

The Read instruction is initiated by executing an 8-bit command, 03H, followed by address bits [A23-

A0]. CE# must remain active low for the duration of the Read cycle. See Figure 5 for the Read

sequence.

Figure 5: Read Sequence

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

and Device ID output stream is continuous until terminated by a low to high transition on CE#

12. Device ID = 43H for SST25LF020A

1242 F04.0

CE#

SCK

ADD.

012345678

ADD. ADD.

HIGH IMPEDANCE

15 16 23 24 31 32 39 40 7047 48 55 56 63 64

N+2 N+3 N+4N N+1

DOUT

MSB MSB

MSB

MODE 0

MODE 3

DOUT DOUT DOUT DOUT

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

High-Speed-Read (33 MHz)

The High-Speed-Read instruction supporting up to 33 MHz is initiated by executing an 8-bit command,

0BH, followed by address bits [A23-A0] and a dummy byte. CE# must remain active low for the duration

of the High-Speed-Read cycle. See Figure 6 for the High-Speed-Read sequence.

Following a dummy byte (8 clocks input dummy cycle), the High-Speed-Read instruction outputs the

data starting from the specified address location. The data output stream is continuous through all

addresses until terminated by a low to high transition on CE#. The internal address pointer will auto-

matically increment until the highest memory address is reached. Once the highest memory address is

reached, the address pointer will automatically increment to the beginning (wrap-around) of the

address space, i.e. for 2 Mbit density, once the data from address location 03FFFFH has been read,

the next output will be from address location 000000H.

Figure 6: High-Speed-Read Sequence

Byte-Program

The Byte-Program instruction programs the bits in the selected byte to the desired data. The selected

byte must be in the erased state (FFH) when initiating a Program operation. A Byte-Program instruction

applied to a protected memory area will be ignored.

Prior to any Write operation, the Write-Enable (WREN) instruction must be executed. CE# must remain

active low for the duration of the Byte-Program instruction. The Byte-Program instruction is initiated by

executing an 8-bit command, 02H, followed by address bits [A23-A0]. Following the address, the data is

input in order from MSB (bit 7) to LSB (bit 0). CE# must be driven high before the instruction is exe-

cuted. The user may poll the Busy bit in the software status register or wait TBP for the completion of

the internal self-timed Byte-Program operation. See Figure 7 for the Byte-Program sequence.

Figure 7: Byte-Program Sequence

1242 F05.0

CE#

SCK

ADD.

012345678

ADD. ADD.0B

HIGH IMPEDANCE

15 16 23 24 31 32 39 40 47 48 55 56 63 64

N+2 N+3 N+4

NN+1

MSB

MODE 0

MODE 3

DOUT DOUT DOUT DOUT

71 72

DOUT

Note: X = Dummy Byte: 8 Clocks Input Dummy Cycle (VIL or VIH)

1242 F06.0

CE#

SCK

ADD.

012345678

ADD. ADD. DIN

HIGH IMPEDANCE

15 16 23 24 31 32 39

MODE 0

MODE 3

MSBMSB

MSB LSB

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Auto Address Increment (AAI) Program

The AAI program instruction allows multiple bytes of data to be programmed without re-issuing the

next sequential address location. This feature decreases total programming time when the entire mem-

ory array is to be programmed. An AAI program instruction pointing to a protected memory area will be

ignored. The selected address range must be in the erased state (FFH) when initiating an AAI program

instruction.

Prior to any write operation, the Write-Enable (WREN) instruction must be executed. The AAI program

instruction is initiated by executing an 8-bit command, AFH, followed by address bits [A23-A0]. Follow-

ing the addresses, the data is input sequentially from MSB (bit 7) to LSB (bit 0). CE# must be driven

high before the AAI program instruction is executed. The user must poll the BUSY bit in the software

status register or wait TBP for the completion of each internal self-timed Byte-Program cycle. Once the

device completes programming byte, the next sequential address may be program, enter the 8-bit

command, AFH, followed by the data to be programmed. When the last desired byte had been pro-

grammed, execute the Write-Disable (WRDI) instruction, 04H, to terminate AAI. After execution of the

WRDI command, the user must poll the Status register to ensure the device completes programming.

See Figure 8 for AAI programming sequence.

There is no wrap mode during AAI programming; once the highest unprotected memory address is

reached, the device will exit AAI operation and reset the Write-Enable-Latch bit (WEL = 0).

Figure 8: Auto Address Increment (AAI) Program Sequence

CE#

SCK

A[23:16] A[15:8] A[7:0]

AF Data Byte 1 AF DataByte2

CE#

SCK

Write Disable (WRDI)

Instruction to terminate

AAI Operation

Read Status Register (RDSR)

Instruction to verify end of

AAI Operation

04Last Data ByteAF 05

DOUT

MODE 3

MODE 0

TBP TBP

TBP

1242 F07.0

012345678 32333435363738391516 2324 31 0123456789101112131415 01

012345670123456789101112131415 0123456789101112131415

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Sector-Erase

The Sector-Erase instruction clears all bits in the selected 4 KByte sector to FFH. A Sector-Erase

instruction applied to a protected memory area will be ignored. Prior to any Write operation, the Write-

Enable (WREN) instruction must be executed. CE# must remain active low for the duration of the any

command sequence. The Sector-Erase instruction is initiated by executing an 8-bit command, 20H, fol-

lowed by address bits [A23-A0]. Address bits [AMS-A12](A

MS = Most Significant address) are used to

determine the sector address (SAX), remaining address bits can be VIL or VIH. CE# must be driven high

before the instruction is executed. The user may poll the Busy bit in the software status register or wait

TSE for the completion of the internal self-timed Sector-Erase cycle. See Figure 9 for the Sector-Erase

sequence.

Figure 9: Sector-Erase Sequence

Block-Erase

The Block-Erase instruction clears all bits in the selected 32 KByte block to FFH. A Block-Erase

instruction applied to a protected memory area will be ignored. Prior to any Write operation, the Write-

Enable (WREN) instruction must be executed. CE# must remain active low for the duration of any com-

mand sequence. The Block-Erase instruction is initiated by executing an 8-bit command, 52H, followed

by address bits [A23-A0]. Address bits [AMS-A15](A

MS = Most significant address) are used to deter-

mine block address (BAX), remaining address bits can be VIL or VIH. CE# must be driven high before the

instruction is executed. The user may poll the Busy bit in the software status register or wait TBE for the com-

pletion of the internal self-timed Block-Erase cycle. See Figure 10 for the Block-Erase sequence.

Figure 10:Block-Erase Sequence

CE#

SCK

ADD.

012345678

ADD. ADD.

HIGH IMPEDANCE

15 16 23 24 31

MODE 0

MODE 3

1242 F08.0

MSBMSB

CE#

SCK

ADD.

012345678

ADD. ADD.

HIGH IMPEDANCE

15 16 23 24 31

MODE 0

MODE 3

1242 F09.0

MSB MSB

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Chip-Erase

The Chip-Erase instruction clears all bits in the device to FFH. A Chip-Erase instruction will be ignored

if any of the memory area is protected. Prior to any Write operation, the Write-Enable (WREN) instruction

must be executed. CE# must remain active low for the duration of the Chip-Erase instruction sequence.

The Chip-Erase instruction is initiated by executing an 8-bit command, 60H. CE# must be driven high

before the instruction is executed. The user may poll the Busy bit in the software status register or wait TCE

for the completion of the internal self-timed Chip-Erase cycle. See Figure 11 for the Chip-Erase

sequence.

Figure 11:Chip-Erase Sequence

Read-Status-Register (RDSR)

The Read-Status-Register (RDSR) instruction allows reading of the status register. The status register

may be read at any time even during a Write (Program/Erase) operation. When a Write operation is in

progress, the Busy bit may be checked before sending any new commands to assure that the new

commands are properly received by the device. CE# must be driven low before the RDSR instruction is

entered and remain low until the status data is read. Read-Status-Register is continuous with ongoing

clock cycles until it is terminated by a low to high transition of the CE#. See Figure 12 for the RDSR

instruction sequence.

Figure 12:Read-Status-Register (RDSR) Sequence

CE#

SCK

01234567

HIGH IMPEDANCE

MODE 0

MODE 3

1242 F10.0

MSB

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

1242 F11.0

MODE 3

SCK

CE#

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

MODE 0

HIGH IMPEDANCE

Status

MSB

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Write-Enable (WREN)

The Write-Enable (WREN) instruction sets the Write-Enable-Latch bit to 1 allowing Write operations to

occur. The WREN instruction must be executed prior to any Write (Program/Erase) operation. CE#

must be driven high before the WREN instruction is executed.

Figure 13:Write Enable (WREN) Sequence

Write-Disable (WRDI)

The Write-Disable (WRDI) instruction resets the Write-Enable-Latch bit and AAI bit to 0 disabling any

new Write operations from occurring. CE# must be driven high before the WRDI instruction is exe-

cuted.

Figure 14:Write Disable (WRDI) Sequence

Enable-Write-Status-Register (EWSR)

The Enable-Write-Status-Register (EWSR) instruction arms the Write-Status-Register (WRSR)

instruction and opens the status register for alteration. The Enable-Write-Status-Register instruction

does not have any effect and will be wasted, if it is not followed immediately by the Write-Status-Regis-

ter (WRSR) instruction. CE# must be driven low before the EWSR instruction is entered and must be

driven high before the EWSR instruction is executed.

CE#

SCK

01234567

HIGH IMPEDANCE

MODE 0

MODE 3

1242 F12.0

MSB

CE#

SCK

01234567

HIGH IMPEDANCE

MODE 0

MODE 3

1242 F13.0

MSB

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Write-Status-Register (WRSR)

The Write-Status-Register instruction works in conjunction with the Enable-Write-Status-Register

(EWSR) instruction to write new values to the BP1, BP0, and BPL bits of the status register. The Write-

Status-Register instruction must be executed immediately after the execution of the Enable-Write-Sta-

tus-Register instruction (very next instruction bus cycle). This two-step instruction sequence of the

EWSR instruction followed by the WRSR instruction works like SDP (software data protection) com-

mand structure which prevents any accidental alteration of the status register values. The Write-Sta-

tus-Register instruction will be ignored when WP# is low and BPL bit is set to “1”. When the WP# is

low, the BPL bit can only be set from “0” to “1” to lock-down the status register, but cannot be reset

from “1” to “0”. When WP# is high, the lock-down function of the BPL bit is disabled and the BPL, BP0,

and BP1 bits in the status register can all be changed. As long as BPL bit is set to 0 or WP# pin is

driven high (VIH) prior to the low-to-high transition of the CE# pin at the end of the WRSR instruction,

the BP0, BP1, and BPL bit in the status register can all be altered by the WRSR instruction. In this

case, a single WRSR instruction can set the BPL bit to “1” to lock down the status register as well as

altering the BP0 and BP1 bit at the same time. See Table 2 for a summary description of WP# and BPL

functions. CE# must be driven low before the command sequence of the WRSR instruction is entered

and driven high before the WRSR instruction is executed. See Figure 15 for EWSR and WRSR instruc-

tion sequences.

Figure 15:Enable-Write-Status-Register (EWSR) and Write-Status-Register (WRSR)

Sequence

1242 F14.0

MODE 3

HIGH IMPEDANCE

MODE 0

STATUS

76543210

MSBMSBMSB

MODE 3

SCK

CE#

MODE 0

0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Read-ID

The Read-ID instruction identifies the devices as SST25LF020A and manufacturer as SST. The device

information can be read from executing an 8-bit command, 90H or ABH, followed by address bits [A23-

A0]. Following the Read-ID instruction, the manufacturer’s ID is located in address 00000H and the

device ID is located in address 00001H. Once the device is in Read-ID mode, the manufacturer’s and

device ID output data toggles between address 00000H and 00001H until terminated by a low to high

transition on CE#.

Figure 16:Read-ID Sequence

Table 6: Product Identification

Address Data

Manufacturer’s ID 00000H BFH

Device ID

SST25LF020A 00001H 43H

T6.0 25080

1242 F15.0

CE#

SCK

012345678

00 ADD1

90 or AB

HIGH IMPEDANCE

15 16 23 24 31 32 39 40 47 48 55 56 63

BF Device ID BF Device ID

Note: The manufacturer s and device ID output stream is continuous until terminated by a low to high transition on CE#.

1. 00H will output the manfacturer s ID first and 01H will output device ID first before toggling between the two.

HIGH

IMPEDANCE

MODE 3

MODE 0

MSB MSB

MSB

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Electrical Specifications

Absolute Maximum Stress Ratings (Applied conditions greater than those listed under “Absolute Maxi-

mum Stress Ratings” may cause permanent damage to the device. This is a stress rating only and functional

operation of the device at these conditions or conditions greater than those defined in the operational sections

of this data sheet is not implied. Exposure to absolute maximum stress rating conditions may affect device reli-

ability.)

Temperature Under Bias .............................................. -55°C to +125°C

Storage Temperature................................................. -65°C to +150°C

D. C. Voltage on Any Pin to Ground Potential .............................-0.5V to VDD+0.5V

Transient Voltage (<20 ns) on Any Pin to Ground Potential ..................-2.0V to VDD+2.0V

Package Power Dissipation Capability (Ta = 25°C)................................... 1.0W

Surface Mount Solder Reflow Temperature ...........................260°C for 10 seconds

Output Short Circuit Current1................................................... 50mA

1. Output shorted for no more than one second. No more than one output shorted at a time.

Table 7: Operating Range

Range Ambient Temp VDD

Commercial 0°C to +70°C 3.0-3.6V

Industrial -40°C to +85°C 3.0-3.6V

Extended -20°C to +85°C 3.0-3.6V

T7.1 25080

Table 8: AC Conditions of Test1

1. See Figures 21 and 22

Input Rise/Fall Time Output Load

5ns CL=30pF

T8.1 25080

Table 9: DC Operating Characteristics VDD = 3.0-3.6V

Symbol Parameter

Limits

Test ConditionsMin Max Units

IDDR Read Current 10 mA CE#=0.1 VDD/0.9 VDD@20 MHz, SO=open

IDDW Program and Erase Current 30 mA CE#=VDD

ISB Standby Current 15 µA CE#=VDD,V

IN=VDD or VSS

ILI Input Leakage Current 1 µA VIN=GND to VDD,V

DD=VDD Max

ILO Output Leakage Current 1 µA VOUT=GND to VDD,V

DD=VDD Max

VIL Input Low Voltage 0.8 V VDD=VDD Min

VIH Input High Voltage 0.7 VDD VV

DD=VDD Max

VOL Output Low Voltage 0.2 V IOL=100 µA, VDD=VDD Min

VOH Output High Voltage VDD-0.2 V IOH=-100 µA, VDD=VDD Min

T9.0 25080

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Table 10:Recommended System Power-up Timings

Symbol Parameter Minimum Units

TPU-READ1

1. This parameter is measured only for initial qualification and after a design or process change that could affect this

parameter.

VDD Min to Read Operation 10 µs

TPU-WRITE1VDD Min to Write Operation 10 µs

T10.0 25080

Table 11:Capacitance (Ta = 25°C, f=1 Mhz, other pins open)

Parameter Description Test Condition Maximum

COUT1

1. This parameter is measured only for initial qualification and after a design or process change that could affect this

parameter.

Output Pin Capacitance VOUT =0V 12pF

CIN1Input Capacitance VIN =0V 6pF

T11.0 25080

Table 12:Reliability Characteristics

Symbol Parameter Minimum Specification Units Test Method

NEND1

1. This parameter is measured only for initial qualification and after a design or process change that could affect this

parameter.

Endurance 10,000 Cycles JEDEC Standard A117

TDR1Data Retention 100 Years JEDEC Standard A103

ILTH1Latch Up 100 + IDD mA JEDEC Standard 78

T12.0 25080

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Table 13:AC Operating Characteristics VDD = 3.0-3.6V

Limits

20 MHz 33 MHz

Symbol Parameter Min Max Min Max Units

FCLK Serial Clock Frequency 20 33 MHz

TSCKH Serial Clock High Time 20 13 ns

TSCKL Serial Clock Low Time 20 13 ns

TCES1CE# Active Setup Time 20 12 ns

TCEH1CE# Active Hold Time 20 12 ns

TCHS1CE# Not Active Setup Time 10 10 ns

TCHH1CE# Not Active Hold Time 10 10 ns

TCPH CE# High Time 100 100 ns

TCHZ CE# High to High-Z Output 20 14 ns

TCLZ SCK Low to Low-Z Output 0 0 ns

TDS Data In Setup Time 5 3 ns

TDH Data In Hold Time 5 3 ns

THLS HOLD# Low Setup Time 10 10 ns

THHS HOLD# High Setup Time 10 10 ns

THLH HOLD# Low Hold Time 15 10 ns

THHH HOLD# High Hold Time 10 10 ns

THZ HOLD# Low to High-Z Output 20 14 ns

TLZ HOLD# High to Low-Z Output 20 14 ns

TOH Output Hold from SCK Change 0 0 ns

TVOutput Valid from SCK 20 12 ns

TSE Sector-Erase 25 25 ms

TBE Block-Erase 25 25 ms

TSCE Chip-Erase 100 100 ms

TBP Byte-Program 20 20 µs

T13.0 25080

1. Relative to SCK.

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Figure 17:Serial Input Timing Diagram

Figure 18:Serial Output Timing Diagram

HIGH-Z HIGH-Z

CE#

SCK

MSB LSB

TDS TDH

TCHH

TCES TCEH TCHS

TSCKR

TSCKF

TCPH

1242 F16.0

1242 F17.0

CE#

SCK

MSB

TCLZ

TSCKH

TCHZ

TOH

TSCKL

LSB

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Figure 19:Hold Timing Diagram

Figure 20:Power-up Timing Diagram

THZ TLZ

THHH THLS

THLH

THHS

1242 F18.0

HOLD#

CE#

SCK

Time

VDD Min

VDD Max

VDD

Device fully accessible

TPU-READ

TPU-WRITE

Chip selection is not allowed.

All commands are rejected by the device.

1242 F19.0

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Figure 21:AC Input/Output Reference Waveforms

Figure 22:A Test Load Example

1242 F20.0

REFERENCE POINTS OUTPUTINPUT

VHT

VLT

VHT

VLT

VIHT

VILT

AC test inputs are driven at VIHT (0.9VDD) for a logic “1” and VILT (0.1VDD) for a logic “0”. Mea-

surement reference points for inputs and outputs are VHT (0.7VDD) and VLT (0.3VDD). Input rise

and fall times (10% 90%) are <5 ns.

Note: VHT -V

HIGH Test

VLT -V

LOW Test

VIHT -V

INPUT HIGH Test

VILT -V

INPUT LOW Test

1242 F21.0

TO TESTER

TO DUT

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Product Ordering Information

Valid combinations for SST25LF020A

SST25LF020A-33-4C-SAE SST25LF020A-33-4C-QAE

SST25LF020A-33-4I-SAE SST25LF020A-33-4I-QAE

SST25LF020A-33-4E-SAE SST25LF020A-33-4E-QAE

Note:Valid combinations are those products in mass production or will be in mass production. Consult your SST

sales representative to confirm availability of valid combinations and to determine availability of new combi-

nations.

SST 25 LF 020A - 33 - 4I - QAE

XX XX XXXX - XX - XX -XXX

Environmental Attribute

E1= non-Pb

Package Modifier

A = 8 leads or contacts

Package Type

S = SOIC 150 mil body width

Q = WSON

Operation Temperature

C = Commercial = 0°C to +70°C

I = Industrial = -40°C to +85°C

E = Extended = -20°C to +85°C

Minimum Endurance

4 = 10,000 cycles

Operating Frequency

33 = 33 MHz

Device Density

020 = 2 Mbit

Voltage

L = 3.0-3.6V

Product Series

25 = Serial Peripheral Interface

flash memory

1. Environmental suffix “E” denotes non-Pb sol-

der.

SST non-Pb solder devices are “RoHS Com-

pliant”.

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Packaging Diagrams

Figure 23: 8-lead Small Outline Integrated Circuit (SOIC) 150 mil body width (4.9mm x 6mm)

SST Package Code: SA

08-soic-5x6-SA-8

Note: 1. Complies with JEDEC publication 95 MS-012 AA dimensions,

although some dimensions may be more stringent.

2. All linear dimensions are in millimeters (max/min).

3. Coplanarity: 0.1 mm

4. Maximum allowable mold flash is 0.15 mm at the package ends and 0.25 mm between leads.

TOP VIEW SIDE VIEW

END VIEW

5.0

4.8

6.20

5.80

4.00

3.80

Pin #1

Identifier

0.51

0.33

1.27 BSC

0.25

0.10

1.75

1.35

7°

4 places

0.25

0.19

1.27

0.40

45° 7°

4 places

0°

8°

1mm

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Figure 24:8-contact Very-very-thin Small Outline No-lead (WSON)

SST Package Code: QA

Note: 1. All linear dimensions are in millimeters (max/min).

2. Untoleranced dimensions (shown with box surround)

are nominal target dimensions.

3. The external paddle is electrically connected to the

die back-side and possibly to certain VSS leads.

This paddle can be soldered to the PC board;

it is suggested to connect this paddle to the VSS of the unit.

Connection of this paddle to any other voltage potential can

result in shorts and/or electrical malfunction of the device.

8-wson-5x6-QA-9.0

4.0

1.27 BSC

Pin #1

0.48

0.35

0.076

3.4

5.00 ±0.10

6.00 ± 0.10 0.05 Max

0.70

0.50

0.80

0.70

0.80

0.70

Pin #1

Corner

TOP VIEW BOTTOM VIEW

CROSS SECTION

SIDE VIEW

1mm

0.2

2 Mbit SPI Serial Flash

SST25LF020A

Not Recommended for New Designs

Microchip Technology Company

Table 14:Revision History

Revision Description Date

00 •Initial release of S71242 Aug 2003

01 •Added new 8-SOIC (S2A) package and associated MPNs Oct 2003

02 •2004 Data Book

•Updated the Package Outline for S2A

Dec 2003

03 •Document status changed from “Advance Information” to “Preliminary

Specifications”

•Added Commercial and Extended temperatures and associated MPNs

Jun 2004

04 •Revised Absolute Max. Stress Ratings for Surface Mount Solder Reflow

Temp.

•Migrated document from Preliminary Specifications to Data Sheet

Nov 2005

05 •Updated QA package drawing to version 9.

•Removed leaded part numbers.

•Added footnote to Product Ordering Information section.

Jan 2006

06 •End of life all valid combinations of SST25LF040A. See S71242(01) Mar 2009

07 •Removed 4Mbit information inadvertently missed in last EOL revision Jan 2010

A•Applied new document format

•Released document under letter revision system

•Updated Spec number from S71242 to DS25080

Nov 2011

SST, Silicon Storage Technology, the SST logo, SuperFlash, MTP, and FlashFlex are registered trademarks of Silicon Storage Tech-

nology, Inc. MPF, SQI, Serial Quad I/O, and Z-Scale are trademarks of Silicon Storage Technology, Inc. All other trademarks and

registered trademarks mentioned herein are the property of their respective owners.

Specifications are subject to change without notice. Refer to www.microchip.com for the most recent documentation. For the most current

package drawings, please see the Packaging Specification located at http://www.microchip.com/packaging.

Memory sizes denote raw storage capacity; actual usable capacity may be less.

SST makes no warranty for the use of its products other than those expressly contained in the Standard Terms and Conditions of

Sale.

For sales office locations and information, please see www.microchip.com.

Silicon Storage Technology, Inc.

A Microchip Technology Company

www.microchip.com

ISBN:978-1-61341-683-9