AT25SL128A
128-Mbit, 1.7V Minimum
SPI Serial Flash Memory with Dual I/O, Quad I/O and QPI Support
Features
Single 1.7V - 2.0V Supply
Serial Peripheral Interface (SPI) and Quad Peripheral Interface (QPI) Compatible
Supports SPI Modes 0 and 3
Supports Dual Output Read and Quad I/O Program and Read
Supports QPI Program and Read
133 MHz Maximum Operating Frequency
Clock-to-Output (tV1) of 6 ns
Up tp 65 MB/s continuous data transfer rate
Full Chip Erase
Flexible, Optimized Erase Architecture for Code and Data Storage Applications
0.6 ms Typical Page Program (256 Bytes) Time
60 ms Typical 4-Kbyte Block Erase Time
200 ms Typical 32-Kbyte Block Erase Time
350 ms Typical 64-Kbyte Block Erase Time
Hardware Controlled Locking of Status Registers via WP Pin
4 Kbit secured One-Time Programmable Security Register
Hardware Write Protection
Serial Flash Discoverable Parameters (SFDP) Register
Flexible Programming
Byte/Page Program (1 to 256 Bytes)
Dual or Quad Input Byte/Page Program (1 to 256 Bytes)
Erase/Program Suspend and Resume
JEDEC Standard Manufacturer and Device ID Read Methodology
Low Power Dissipation
2 µA Deep Power-Down Current (Typical)
10 µA Standby current (Typical)
5 mA Active Read Current (Typical)
Endurance: 100,000 program/erase cycles (4 KB, 32 KB or 64 KB blocks)
Data Retention: 20 Years
Industrial Temperature Range: -40°C to +85°C
Industry Standard Green (Pb/Halide-free/RoHS Compliant) Package Options
8-lead SOIC (208-mil)
8-pad DFN (6 x 5 x 0.6 mm)
21-ball die Ball Grid Array (dBGA - WLCSP)
Die in Wafer Form
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1.
Introduction
The Adesto® AT25SL128A is a serial interface Flash memory device designed for use in a wide variety of high-volume
consumer based applications in which program code is shadowed from Flash memory into embedded or external RAM
for execution. The flexible erase architecture of the AT25SL128A is ideal for data storage as well, eliminating the need
for additional data storage devices.
The erase block sizes of the AT25SL128A have been optimized to meet the needs of today's code and data storage
applications. By optimizing the size of the erase blocks, the memory space can be used much more efficiently. Because
certain code modules and data storage segments must reside by themselves in their own erase regions, the wasted and
unused memory space that occurs with large block erase Flash memory devices can be greatly reduced. This increased
memory space efficiency allows additional code routines and data storage segments to be added while still maintaining
the same overall device density.
SPI clock frequencies of up to 133 MHz are supported allowing equivalent clock rates of 266 MHz for Dual Output and
532 MHz for Quad Output when using the QPI and Fast Read Dual/Quad I/O instructions.The AT25SL128A array is
organized into 65,536 programmable pages of 256-bytes each. Up to 256 bytes can be programmed at a time using the
Page Program instructions. Pages can be erased 4KB Block, 32KB Block, 64KB Block or the entire chip.
The devices operate on a single 1.7V to 2.0V power supply with current consumption as low as 5mA active and 2µA for
Deep Power Down. All devices offered in space-saving packages. The device supports JEDEC standard manufacturer
and device identification with a 4K-bit Secured OTP.
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2.
Pinouts and Pin Descriptions
The following figures show the available package types.
Figure 1-1. 8-SOIC (Top View)
CS
SO (IO1)
WP (IO2)
GND
1
2
3
4
Figure 1-2. 8-UDFN (Top View)
VCC
HOLD (IO3)
SCK
SI (IO0)
8
7
6
5
CS
SO (IO1)
WP (IO2)
GND
1
8
2
7
3
6
4
5
VCC
HOLD (IO3)
SCK
SI (IO0)
Figure 1-3. 21-WLCSP (Bottom View)
6
5
4
3
CS
Vcc
2
1
A
B
I/O1(SO) I/O3(HOLD)
C
I/O2(WP)
SCK
D
GND
I/O0(SI)
E
F
During all operations, VCC must be held stable and within the specified valid range: VCC (min) to VCC (max).
All of the input and output signals must be held high or low (according to voltages of VIH, VOH, VIL or VOL.
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Table 1-1.
Pin Descriptions
Symbol
Name and Function
CS
CHIP SELECT
Asserted
State
Type
Low
Input
-
Input
-
Input/Output
-
Input/Output
-
Input/Output
When this input signal is high, the device is deselected and serial data output pins are at
high impedance. Unless an internal program, erase or write status register cycle is in
progress, the device will be in the standby power mode (this is not the deep power down
mode). Driving Chip Select (CS) low enables the device, placing it in the active power
mode. After power-up, a falling edge on Chip Select (CS) is required prior to the start of
any instruction.
SCK
SERIAL CLOCK
This input signal provides the timing for the serial interface. Instructions, addresses, or
data present at serial data input are latched on the rising edge of Serial Clock (SCK).
Data are shifted out on the falling edge of the Serial Clock (SCK).
SI (I/O0)
SERIAL INPUT
The SI pin is used to shift data into the device. The SI pin is used for all data input
including command and address sequences. Data on the SI pin is always latched in on
the rising edge of SCK.
With the Dual-Output and Quad-Output Read commands, the SI Pin becomes an output
pin (I/O0) in conjunction with other pins to allow two or four bits of data on (I/O3-0) to be
clocked in on every falling edge of SCK
To maintain consistency with the SPI nomenclature, the SI (I/O0) pin is referenced as the
SI pin unless specifically addressing the Dual-I/O and Quad-I/O modes in which case it is
referenced as I/O0.
Data present on the SI pin is ignored whenever the device is deselected (CS is
deasserted).
SO (I/O1)
SERIAL OUTPUT
The SO pin is used to shift data out from the device. Data on the SO pin is always
clocked out on the falling edge of SCK.
With the Dual-Output Read commands, the SO Pin remains an output pin (I/O0) in
conjunction with other pins to allow two bits of data on (I/O1-0) to be clocked in on every
falling edge of SCK
To maintain consistency with the SPI nomenclature, the SO (I/O1) pin is referenced as
the SO pin unless specifically addressing the Dual-I/O modes in which case it is
referenced as I/O1. The SO pin is in a high-impedance state whenever the device is
deselected (CS is deasserted).
WP (I/O2)
WRITE PROTECT
The Write Protect (WP) pin can be used to protect the Status Register against data
modification. Used in company with the Status Register's Block Protect (SEC, TB, BP2, BP1
and BP0) bits and Status Register Protect SRP) bits, a portion or the entire memory array can
be hardware protected. The WP pin is active low. When the QE bit of Status Register-2 is set
for Quad I/O, the WP pin (Hardware Write Protect) function is not available since this pin is
used for IO2. See figures 1-1, 1-2, and 1-3 for the pin configuration of Quad I/O and QPI
operation.
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Table 1-1.
Pin Descriptions (Continued)
Symbol
Name and Function
HOLD
HOLD
(I/O3)
The HOLD pin is used to temporarily pause serial communication without deselecting or
resetting the device. While the HOLD pin is asserted, transitions on the SCK pin and data on
the SI pin are ignored and the SO pin is placed in a high-impedance state.
Asserted
State
Type
-
Input/Output
The CS pin must be asserted, and the SCK pin must be in the low state in order for a
Hold condition to start. A Hold condition pauses serial communication only and does not
have an effect on internally self-timed operations such as a program or erase cycle.
With the Quad-Input Byte/Page Program command, the HOLD pin becomes an input pin
(I/O3) and with other pins, allows four bits (on I/O3-0) of data to be clocked in on every
rising edge of SCK. With the Quad-Output Read commands, the HOLD Pin becomes an
output pin (I/O3) in conjunction with other pins to allow four bits of data on (I/O33-0) to be
clocked in on every falling edge of SCK. To maintain consistency with SPI nomenclature,
the HOLD (I/O3) pin is referenced as the HOLD pin unless specifically addressing the
Quad-I/O modes in which case it is referenced as I/O3. The HOLD pin is internally pulledhigh and may be left floating if the Hold function is not used. However, it is recommended
that the HOLD pin also be externally connected to VCC whenever possible. See figures 11, 1-2, and 1-3 for the pin configuration of Quad I/O and QPI operation.
VCC
DEVICE POWER SUPPLY: VCC is the supply voltage. It is the single voltage used for all
device functions including read, program, and erase. The VCC pin is used to supply the
source voltage to the device. Operations at invalid VCC voltages may produce spurious results
and should not be attempted.
-
Power
GND
GROUND: VSS is the reference for the VCC supply voltage. The ground reference for the
power supply. GND should be connected to the system ground.
-
Power
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Block Diagram
Figure 2-1 shows a block diagram of the AT25SL128A serial Flash.
Figure 2-1. AT25SL128A Block Diagram
Control and
Protection Logic
CS
I/O Buffers
and Latches
SRAM
Data Buffer
SCK
SI (I/O0)
SO (I/O1)
WP (I/O2)
Interface
Control
And
Logic
Address Latch
2.
Y-Decoder
Y-Gating
X-Decoder
Flash
Memory
Array
HOLD
(I/O3)
Note: I/O3-0 pin naming convention is used for Dual-I/O and Quad-I/O commands.
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Memory Array
To provide the greatest flexibility, the memory array of the AT25SL128A can be erased in four levels of granularity
including a full chip erase. The size of the erase blocks is optimized for both code and data storage applications, allowing
both code and data segments to reside in their own erase regions. The Memory Architecture Diagram illustrates the
breakdown of each erase level.
Figure 3-1. Memory Architecture Diagram
Block Erase Detail
Block
511
Sector
255
Block
510
Block
509
Sector
254
•••
Block
508
Block
1
Sector
0
Block
0
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
1-256 Byte
FFFFFFh – FFF000h
FFEFFFh – FFE000h
FFDFFFh – FFD000h
FFCFFFh – FFC000h
FFBFFFh – FFB000h
FFAFFFh – FFA000h
FF9FFFh – FF9000h
FF8FFFh – FF8000h
FF7FFFh – FF7000h
FF6FFFh – FF6000h
FF5FFFh – FF5000h
FF4FFFh – FF4000h
FF3FFFh – FF3000h
FF2FFFh – FF2000h
FF1FFFh – FF1000h
FF0FFFh – FF0000h
FEFFFFh – FEF000h
FEEFFFh – FEE000h
FEDFFFh – FED000h
FECFFFh – FEC000h
FEBFFFh – FEB000h
FEAFFFh – FEA000h
FE9FFFh – FE9000h
FE8FFFh – FE8000h
FE7FFFh – FE7000h
FE6FFFh – FE6000h
FE5FFFh – FE5000h
FE4FFFh – FE4000h
FE3FFFh – FE3000h
FE2FFFh – FE2000h
FE1FFFh – FE1000h
FE0FFFh – FE0000h
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
4KB
00FFFFh
00EFFFh
00DFFFh
00CFFFh
00BFFFh
00AFFFh
009FFFh
008FFFh
007FFFh
006FFFh
005FFFh
004FFFh
003FFFh
002FFFh
001FFFh
000FFFh
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
00F000h
00E000h
00D000h
00C000h
00B000h
00A000h
009000h
008000h
007000h
006000h
005000h
004000h
003000h
002000h
001000h
000000h
Page Address
Range
FFFFFFh – FFFF00h
FFFEFFh – FFFE00h
FFFDFFh - FFFD00h
FFFCFFh – FFFC00h
FFFBFFh – FFFB00h
FFFAFFh – FFFA00h
FFF9FFh – FFF900h
FFF8FFh – FFF800h
FFF7FFh – FFF700h
FFF6FFh – FFF600h
FFF5FFh – FFF500h
FFF4FFh – FFF400h
FFF3FFh – FFF300h
FFF2FFh – FFF200h
FFF1FFh – FFF100h
FFF0FFh – FFF000h
FFEFFFh – FFEF00h
FFEEFFh – FFEE00h
FFEDFFh – FFED00h
FFECFFh – FFEC00h
FFEBFFh – FFEB00h
FFEAFFh – FFEA00h
FFE9FFh – FFE900h
FFE8FFh – FFE800h
•••
32KB
Page Program Detail
Block Address
Range
•••
64KB
•••
3.
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
256 Bytes
0017FFh – 001700h
0016FFh – 001600h
0015FFh – 001500h
0014FFh – 001400h
0013FFh – 001300h
0012FFh – 001200h
0011FFh – 001100h
0010FFh – 001000h
000FFFh – 000F00h
000EFFh – 000E00h
000DFFh – 000D00h
000CFFh – 000C00h
000BFFh – 000B00h
000AFFh – 000A00h
0009FFh – 000900h
0008FFh – 000800h
0007FFh – 000700h
0006FFh – 000600h
0005FFh – 000500h
0004FFh – 000400h
0003FFh – 000300h
0002FFh – 000200h
0001FFh – 000100h
0000FFh – 000000h
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4.
Device Operation
4.1
Standard SPI Operation
The AT25SL128A features a serial peripheral interface on four signals: Serial Clock (SCK). Chip Select (CS), Serial
Data Input (SI) and Serial Data Output (SO). Standard SPI instructions use the SI input pin to serially write instructions,
addresses or data to the device on the rising edge of SCK. The SO output pin is used to read data or status from the
device on the falling edge of SCK.
SPI bus operation Modes 0 (0, 0) and 3 (1, 1) are supported. The primary difference between Mode 0 and Mode 3
concerns the normal state of the SCK signal when the SPI bus master is in standby and data is not being transferred
to the Serial Flash. For Mode 0 the SCK signal is normally low on the falling and rising edges of CS. For Mode 3 the
SCK signal is normally high on the falling and rising edges of CS.
4.2
Dual SPI Operation
The AT25SL128A supports Dual SPI operation. This instruction allows data to be transferred to or from the device at
two times the rate of the standard SPI. The Dual Read instruction is ideal for quickly downloading code to RAM upon
power-up (code-shadowing) or for executing non-speed- critical code directly from the SPI bus (XIP). When using Dual
SPI instructions the SI and SO pins become bidirectional I/0 pins; IO0 and IO1.
4.3
Quad SPI Operation
The AT25SL128A supports Quad SPI operation. This instruction allows data to be transferred to or from the device at
four times the rate of the standard SPI. The Quad Read instruction offers a significant improvement in continuous
and random access transfer rates allowing fast code-shadowing to RAM or execution directly from the SPI bus (XIP).
When using Quad SPI instruction the SI and SO pins become bidirectional IO0 and IO1, and the WP and HOLD pins
become IO2 and IO3 respectively. Quad SPI instructions require the non-volatile Quad Enable bit (QE) in Status
Register-2 to be set.
4.4
QPI Operation
The AT25SL128A supports Quad Peripheral Interface (QPI) operation when the device is switched from Standard/
Dual/ Quad SPI mode to QPI mode using the “Enable QPI (38h)” instruction. To enable QPI mode, the non-volatile
Quad Enable bit (QE) in Status Register-2 is required to be set. When using QPI instructions, the SI and SO pins
become bidirectional IO0 and IO1, and the WP and HOLD pins become IO2 and IO3 respectively.
The typical SPI protocol requires that the byte-long instruction code being shifted into the device only via SI pin in eight
serial clocks. The QPI mode utilizes all four IO pins to input the instruction code, thus only two serial clocks are required.
This can significantly reduce the SPI instruction overhead and improve system performance in an XIP environment.
Standard/ Dual/ Quad SPI mode and QPI mode are exclusive. Only one mode can be active at any given time, “Enable
QPI” and “Disable QPI/ Disable QPI 2” instructions are used to switch between these two modes. Upon power-up or after
software reset using “Reset (99h) instruction, the default state of the device is Standard/ Dual/ Quad SPI mode.
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5.
Write Protection
To protect inadvertent writes by the possible noise, several means of protection are applied to the Flash memory.
5.1
Write Protect Features
While Power-on reset, all operations are disabled and no instruction is recognized.
An internal time delay of tPUW can protect the data against inadvertent changes while the power supply is outside
the operating specification. This includes the Write Enable, Page program, Block Erase, Chip Erase, Write Security
Register and the Write Status Register instructions.
For data changes, Write Enable instruction must be issued to set the Write Enable Latch (WEL) bit to “0”. Powerup, Completion of Write Disable, Write Status Register, Page program, Block Erase and Chip Erase are subjected to
this condition.
Using setting the Status Register protect (SRP) and Block protect (SEC, TB, BP2, BP1, and BP0) bits a portion of
memory can be configured as reading only called software protection.
Write Protect (WP) pin can control to change the Status Register under hardware control.
The Deep Power Down mode provides extra protection from unexpected data changes as all instructions are ignored
under this status except for Release Deep Power Down instruction.
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6.
Status Register
The Read Status Register instruction can be used to provide status on the availability of the Flash memory array, if the device
is write enabled or disabled the state of write protection and the Quad SPI setting. The Write Status Register instruction can be
used to configure the devices writes protection features and Quad SPI setting. Write access to the Status Register is controlled
by in some cases of the WP pin.
S7
S6
S5
S4
S3
S2
S1
S0
SRP
SEC
TB
BP2
BP1
BP0
WEL
BUSY
Status
Sector Protect Top/Bottom
Block Protect Block Protect Block Protect
Register
(Non- Volatile) Write Protect (Non- Volatile) (Non- Volatile) (Non- Volatile)
Protect 0 (Non(Non- Volatile)
Volatile)
6.1
Write Enable Erase or Write
Latch
in Progress
S15
S14
S13
S12
S11
S10
S9
S8
SUS
CMP
(R)
(R)
(R)
(R)
QE
SRP1
Suspend
Status
Complement
Protect (NonVolatile)
Reserved
Reserved
Reserved
Reserved
Quad Enable
(Non- Volatile)
Register
Protect 1
(Non- Volatile)
Busy
BUSY is a read only bit in the status register (S0) that is set to a 1 state when the device is executing a Page Program, Erase,
Write Status Register or Write Security Register instruction. During this time the device will ignore further instruction except for
the Read Status Register and Erase / Program Suspend instruction (see tW, tPP, tSE, tBE1, tBE2 and tCE in AC Characteristics).
When the Program, Erase, Write Status Register or Write Security Register instruction has completed, the BUSY bit will be
cleared to a 0 state indicating the device is ready for further instructions.
6.2
Write Enable Latch (WEL)
Write Enable Latch (WEL) is a read only bit in the status register (S1) that is set to a 1 after executing a Write Enable instruction.
The WEL status bit is cleared to a 0 when device is write disabled. A write disable state occurs upon power-up or after any of
the following instructions: Write Disable, Page Program, Erase and Write Status Register.
6.3
Block Protect Bits (BP2, BP1, BP0)
The Block Protect Bits (BP2, BP1, BP0) are non-volatile read/write bits in the status register (S4, S3, and S2) that provide write
protection control and status. Block protect bits can be set using the Write Status Register Instruction (see tW in AC
characteristics). All, none or a portion of the memory array can be protected from Program and Erase instructions (see Status
Register Memory Protection table). The factory default setting for the Block Protection Bits is 0, none of the array protected.
6.4
Top/Bottom Block protect (TB)
The Top/Bottom bit (TB) is non-volatile bits in the status register (S5) that controls if the Block Protect Bits (BP2, BP1, BP0)
protect from the Top (TB = 0) or the Bottom (TB = 1) of the array as shown in the Status Register Memory Protection table. The
factory default setting is TB = 0. The TB bit can be set with the Write Status Register Instruction depending on the state of the
SRP0, SRP1 and WEL bits.
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6.5
Sector/Block Protect (SEC)
The Sector protect bit (SEC) is non-volatile bits in the status register (S6) that controls if the Block Protect Bits (BP2, BP1, BP0)
protect 4KB Sectors (SEC = 1) or 64KB Blocks (SEC = 0) in the Top (TB = 0) or the Bottom (TB = 1) of the array as shown in the
Status Register Memory protection table. The default setting is SEC = 0.
6.6
Status Register Protect (SRP1, SRP0)
The Status Register Protect bits (SRP1 and SRP0) are non-volatile read/write bits in the status register (S8 and S7). The
SRP bits control the method of write protection: software protection, hardware protection, power supply lock-down or one time
programmable (OTP) protection.
Table 6-1.
Encoding of SRP[1:0] Bits and Write Protection
SRP1
SRP0
WP
Status Register
Description
0
0
X
Software Protection
WP pin no control. The register can be written to after a Write
Enable instruction, WEL = 1. [Factory Default]
0
1
0
Hardware Protected
When the WP pin is low the Status Register locked and can
not be written to.
0
1
1
Hardware Unprotected
When WP pin is high the Status register is unlocked and
can be written to after a Write Enable instruction, WEL = 1.
1
0
X
Power Supply Lock-Down Status Register is protected and cannot be written to again
until the next power down, power-up cycle.(1)
1
1
X
One Time Program
Status Register is permanently protected and cannot be
written to.
Note: 1. When SRP1, SRP0=(1,0), a power down, power-up cycle will change SRP1, SRP0 to(0,0) state.
6.7
Quad Enable (QE)
The Quad Enable (QE) bit is a non-volatile read/write bit in the status register (S9) that allows Quad operation.
When the QE bit is set to a 0 state (factory default) the WP pin and HOLD are enabled. When the QE pin is set to a 1 the
Quad IO2 and IO3 pins are enabled. WARNING: The QE bit should never be set to a 1 during standard SPI or Dual
SPI operation if the WP or HOLD pins are tied directly to the power supply or ground.
6.8
Complement Protect (CMP)
The Complement Protect bit (CMP) is a non-volatile read/write bit in the status register (S14). It is used in conjunction
with SEC, TB, BP2, BP1 and BP0 bits to provide more flexibility for the array protection. Once CMP is set to 1, previous
array protection set by SEC, TB, BP2, BP1 and BP0 will be reversed. For instance, when CMP = 0, a top 4KB sector can
be protected while the rest of the array is not; when CMP = 1, the top 4KB sector will become unprotected while the rest
of the array become read-only. Please refer to the Status Register Memory Protection table for details. The default
setting is CMP = 0.
6.9
Erase/Program Suspend Status (SUS)
The Suspend Status bit (SUS) is a read only bit in the status register (S15) that is set to 1 after executing an
Erase/Program Suspend (75h) instruction. The SUS status bit is cleared to 0 by Erase/Program Resume (7Ah)
instruction as well as a power down, power-up cycle.
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Table 6-2.
Status Register Memory Protection (CMP = 0)
Status Register
Memory Protection
SEC
TB
BP2
BP1
BP0
Sector(s)
Addresses
Density
Portion
X
X
0
0
0
NONE
NONE
NONE
NONE
0
0
0
0
1
252 thru 255
FC0000h - FFFFFFh
256KB
Upper 1/64
0
0
0
1
0
248 thru 255
F80000h - FFFFFFh
512KB
Upper 1/32
0
0
0
1
1
240 thru 255
F00000h - FFFFFFh
1MB
Upper 1/16
0
0
1
0
0
224 thru 255
E00000h - FFFFFFh
2MB
Upper 1/8
0
0
1
0
1
192 thru 255
C00000h - FFFFFFh
4MB
Upper 1/4
0
0
1
1
0
128 thru 255
800000h - FFFFFFh
8MB
Upper 1/2
0
1
0
0
1
0 thru 3
000000h - 03FFFFh
256KB
Lower 1/64
0
1
0
1
0
0 thru 7
000000h - 07FFFFh
512KB
Lower 1/32
0
1
0
1
1
0 thru 15
000000h - 0FFFFFh
1MB
Lower 1/16
0
1
1
0
0
0 thru 31
000000h - 1FFFFFh
2MB
Lower 1/8
0
1
1
0
1
0 thru 63
000000h - 3FFFFFh
4MB
Lower 1/4
0
1
1
1
0
0 thru 127
000000h - 7FFFFFh
8MB
Lower 1/2
X
X
1
1
1
0 thru 255
000000h - FFFFFFh
16MB
ALL
1
0
0
0
1
255
FFF000h - FFFFFFh
4KB
U – 1/4096 (4)
1
0
0
1
0
255
FFE000h - FFFFFFh
8KB
U – 1/2048
1
0
0
1
1
255
FFC000h - FFFFFFh
16KB
U – 1/1024
1
0
1
0
X
255
FF8000h - FFFFFFh
32KB
U – 1/512
1
1
0
0
1
0
000000h - 000FFFh
4KB
L – 1/4096
1
1
0
1
0
0
000000h - 001FFFh
8KB
L – 1/2048
1
1
0
1
1
0
000000h - 003FFFh
16KB
L – 1/1024
1
1
1
0
X
0
000000h - 007FFFh
32KB
L – 1/512
Note:
1.
X = Don’t care
2.
L = Lower; U = Upper
3.
If any Erase or Program instruction specifies a memory region that contains protected data portion, this instruction will
be ignored.
4.
Note 3 does not apply to this Status Register Bit setting. See Errata 1 in Appendix A for details.
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Table 6-3.
Status Register Memory Protection (CMP = 1)
Status Register
Memory Protection
SEC
TB
BP2
BP1
BP0
Sector(s)
Addresses
Density
Portion
X
X
0
0
0
0 thru 255
000000h - FFFFFFh
16MB
ALL
0
0
0
0
1
0 thru 251
000000h – FBFFFFh
16,128KB
Lower 63/64
0
0
0
1
0
0 and 247
000000h – F7FFFFh
15,872KB
Lower 31/32
0
0
0
1
1
0 thru 239
000000h – EFFFFFh
15MB
Lower 15/16
0
0
1
0
0
0 thru 223
000000h – DFFFFFh
14MB
Lower 7/8
0
0
1
0
1
0 thru 191
000000h – BFFFFFh
12MB
Lower 3/4
0
0
1
1
0
0 thru 127
000000h – 7FFFFFh
8MB
Lower 1/2
0
1
0
0
1
4 thru 255
040000h - FFFFFFh
16,128KB
Upper 63/64
0
1
0
1
0
8 and 255
080000h - FFFFFFh
15,872KB
Upper 31/32
0
1
0
1
1
16 thru 255
100000h - FFFFFFh
15MB
Upper 15/16
0
1
1
0
0
32 thru 255
200000h - FFFFFFh
14MB
Upper 7/8
0
1
1
0
1
64 thru 255
400000h - FFFFFFh
12MB
Upper 3/4
0
1
1
1
0
128 thru 255
800000h - FFFFFFh
8MB
Upper 1/2
X
X
1
1
1
NONE
NONE
NONE
NONE
1
0
0
0
1
0 thru 255
000000h - FFEFFFh
16,380KB
L – 4095/4096
1
0
0
1
0
0 thru 255
000000h - FFDFFFh
16,376KB
L – 2047/2048
1
0
0
1
1
0 thru 255
000000h - FFBFFFh
16,368KB
L – 1023/1024
1
0
1
0
X
0 thru 255
000000h - FF7FFFh
16,352KB
L – 511/512
1
1
0
0
1
0 thru 255
001000h - FFFFFFh
16,380KB
U – 4095/4096 (4)
1
1
0
1
0
0 thru 255
002000h - FFFFFFh
16,376KB
U – 2047/2048
1
1
0
1
1
0 thru 255
004000h - FFFFFFh
16,368KB
U – 1023/1024
1
1
1
0
X
0 thru 255
008000h - FFFFFFh
16,352KB
U – 511/512
Note:
1.
X = don’t care
2.
L = Lower; U = Upper
3.
If any Erase or Program instruction specifies a memory region that contains protected data portion, this instruction will be ignored.
4.
Note 3 does not apply to this Status Register Bit setting. See Errata 2 in Appendix A for details.
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7.
Instructions
Instructions are initiated with the falling edge of Chip Select (CS). The first byte of data clocked into the input pins
(SI or IO [3:0]) provides the instruction code. Data on the SI input is sampled on the rising edge of clock with most
significant bit (MSB) first.
Instructions are completed with the rising edge of edge CS. Clock relative timing diagrams for each instruction are
included in figures 8-1 through 8-66 All read instructions can be completed after any clocked bit. However, all instructions
that Write, Program or Erase must complete on a byte (CS driven high after a full 8-bit have been clocked) otherwise the
instruction will be terminated. This feature further protects the device from inadvertent writes. Additionally, while the
memory is being programmed or erased, or when the Status Register is being written, all instructions except for Read
Register will be ignored until the program or erase cycle has completed.
Table 7-1.
Manufacturer and Device Identification
ID code
7.1
Instruction
Manufacturer ID
Adesto
1Fh
90h, 92h, 94h, 9Fh
Device ID
AT25SL128A
17h
90h, 92h, 94h, ABh
Memory Type ID
SPI / QPI
42h
9Fh
Capacity Type ID
128M
18h
9Fh
Instruction Set Tables
Table 7-2.
Instruction Set Table 1 (SPI Instructions)
Instruction Byte
0
1
2
3
4
5
Clock Number
0-7
8 - 15
16 - 23
24 - 31
32 - 39
40 - 47
Write Enable
06h
Write Enable
(for volatile Status registers)
50h
Write Disable
04h
Read Status Register 1
05h
SR7:SR0 (1)
Read Status Register 2
35h
SR15:SR8(2)
Write Status Register 1
01h
SR7:SR0
Write Status Register 2
31h
SR15:SR8
Read Data
03h
A23:A16
A15:A8
A7:A0
D7:D0
Fast Read Data
0Bh
A23:A16
A15:A8
A7:A0
Dummy
Page Program
02h
Enable QPI
38h
Block Erase (4 KB)
SR15:SR8
A23:A16
A15:A8
A7:A0
20h
A23:A16
A15:A8
A7:A0
Block Erase (32 KB)
52h
A23:A16
A15:A8
A7:A0
Block Erase (64 KB)
D8h
A23:A16
A15:A8
A7:A0
Chip Erase
60h/7Ch
Erase/Program Suspend
75h
D7:D0
D7:D0
(2)
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Table 7-2.
Instruction Set Table 1 (SPI Instructions)
Instruction Byte
0
1
2
3
4
5
Clock Number
0-7
8 - 15
16 - 23
24 - 31
32 - 39
40 - 47
Erase/Program Resume
7Ah
Deep Power Down
B9h
Release from Deep Power
Down/Device ID
ABh
Dummy
Dummy
Dummy
D7:D0(2)
Read Manufacturer ID (3)
90h
00h
00h
00h or 01h
MID7:MID0
DID7:DID0
Read JEDEC ID
9Fh
MID7:MID0
D7:D0
D7:D0
Reset Enable
66h
Reset
99h
Enter Secured OTP
B1h
Exit Secured OTP
C1h
Read Security Register
2Bh
Write Security Register
2Fh
Read Serial Flash
Discovery Parameters
5Ah
A15:A8
A7:A0
Dummy
D7:D0
SC7:SC0 (4)
A23:A16
1.
SR = status register, The Status Register contents and Device ID will repeat continuously until CS terminates the instruction.
2.
At least one byte of data input is required for Page Program, Quad Page Program and Program Security Register, up to 256 bytes ? of data input. If more
than 256 bytes of data are sent to the device, the addressing will wrap to the beginning of the page and overwrite previously sent data.
3.
See Manufacturer and Device Identification table for Device ID information.
4.
SC = security register.
Table 7-3.
Instruction Set Table 1 (Dual SPI Instructions)
Instruction Byte
0
1
2
3
4
5
Clock Number
0-7
8 - 15
16 - 23
24 - 31
32 - 39
40 - 47
Fast Read Dual Output
3Bh
A23:A16
A15:A8
A7:A0
Dummy
D7:D0 (1)
Fast Read Dual I/O
BBh
A23:A8 (2)
A7:A0
D7:D0....(1)
Read Manufacturer ID (3)
92h
0000h
(00h, xxxx) or
01h, xxxx)
MID7:MID0
DID7:DID0(1)
1.
Dual Output data: IO0 = (D6, D4, D2, D0), IO1 = (D7, D5, D3, D1)
2.
Dual input address:
IO0 = A22, A20, A18, A16, A14, A12, A10, A8, A6, A4, A2, A0, M6, M4, M2, M0
IO1 = A23, A21, A19, A17, A15, A13, A11, A9, A7, A5, A3, A1, M7, M5, M3, M1
3.
See Manufacturer and Device Identification table for Device ID information.
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Table 7-4.
Instruction Set Table 3 (Quad SPI Instructions)
Instruction Byte
0
1
2
3
4
5
Clock Number
0-7
8 - 15
16 - 23
24 - 31
32 - 39
40 - 47
Fast Read Quad Output
6Bh
A23:A16
A15:A8
A7:A0
Dummy
D7:D0 (1)
Fast Read Quad I/O
EBh
A23:A0,
M7:M0 (2)
(xxxx,
D7:D0...) (3)
D7:D0....(1)
Quad Page Program
33h
A23:A0
(D7:D0, ...)(1)
Read Quad Manufacturer ID (4)
94h
00_0000h, xx
or
00_00001h, xx
(xxxx,
MID7:MID0)
(xxxx,
DID7:DID0)(3)
Fast Read Quad I/O
EBh
A23:A0
M7:M0(2)
(xx, D7:D0)
D7:D0(1)
Set Burst with Wrap
77h
xxxxxx,
W6:W4 (5)
(xx, D7:D0)
D7:D0
1.
Quad Input/ Output Data
IO0 = (D4, D0...)
IO1 = (D5, D1...)
IO2 = (D6, D2...)
IO3 = (D7, D3...)
2.
Quad Input Address
IO0 = A20, A16, A12, A8, A0, M4, M0
IO1 = A21, A17, A13, A9, A1, M5, M1
IO2 = A22, A18, A14, A10, A2, M6, M2
IO3 = A23, A19, A15, A11, A3, M7, M3
3.
Fast Read Quad I/O Data Output
IO0 = (x, x, x, x, D4, D0...)
IO1 = (x, x, x, x, D5, D1...)
IO2 = (x, x, x, x, D6, D2...)
IO3 = (x, x, x, x, D7, D3...)
4.
See Manufacturer and Device Identification table for Device ID information.
5.
Set Burst With Wrap
IO0 = x, x, x, x, x, x, W4, x
IO1 = x, x, x, x, x, x, W5, x
IO2 = x, x, x, x, x, x, W6, x
IO3 = x, x, x, x, x, x, W7, x
Table 7-5.
Instruction Set Table 4 (QPI Instructions)
Instruction Byte (1)
0
1
2
3
4
5
6
7
8
Clock Number
0, 1
2, 3
4, 5
6, 7
8, 9
10, 11
12, 13
14, 15
16, 17
Write Enable
06h
Write Enable
(for volatile Status registers)
50h
Write Disable
04h
Read Status Register 1
05h
(SR7:SR0) (2)
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Table 7-5.
Instruction Set Table 4 (QPI Instructions)
Instruction Byte (1)
0
1
2
3
4
5
6
7
8
Clock Number
0, 1
2, 3
4, 5
6, 7
8, 9
10, 11
12, 13
14, 15
16, 17
Read Status Register 2
35h
(SR15:SR8)
(2)
Write Status Register 1(2)
01h
(SR7:SR0) (SR15:SR8)
Write Status Register 2
31h
(SR15:SR8)
0Bh
A23:A16
A15:A8
A7:A0
Dummy
Dummy
(D7:D0)
A23:A16
A15:A8
A7:A0
Dummy
Dummy
Dummy (D7:D0)
A23:A16
A15:A8
A7:A0
(D7:D0)
Fast Read Data
up to 80
MHz
up to 104
MHz
Page Program
02h
(3)
Block Erase (4 KB)
20h
A23:A16
A15:A8
A7:A0
Block Erase (32 KB)
52h
A23:A16
A15:A8
A7:A0
Block Erase (64 KB)
D8h
A23:A16
A15:A8
A7:A0
Chip Erase
60h/7Ch
Erase/Program Suspend
75h
Erase/Program Resume
7Ah
Deep Power Down
B9h
Release from Deep
Power Down
ABh
Read Manufacturer/
Device ID (4)
90h
00h
00h
00h or
01h
Read JEDEC ID
9Fh
Enter Secured OTP
B1h
Exit Secured OTP
C1h
Read Security Register
2Bh
Write Security Register
2Fh
Fast Read
Quad I/O
EBh
up to 80
MHz
(MID7:MID0) (D7:D0)
(Mfg ID)
(Mem Typ)
(MID7:
MID0)
(DID7:
DID0)
(D7:D0)
(Cap)
(SC7:SC0) (5)
A23:A16
A15:A8
A7:A0
(M7:M0) Dummy
(D7:D0)
up to 104
MHz
A23:A16
A15:A8
A7:A0
(M7:M0) Dummy
Dummy (D7:D0)
up to 133
MHz
A23:A16
A15:A8
A7:A0
(M7:M0) Dummy
Dummy Dummy (D7:D0)
Reset Enable
66h
Reset
99h
Disable QPI
FFh
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Table 7-5.
Instruction Set Table 4 (QPI Instructions)
Instruction Byte (1)
0
1
2
3
4
5
6
7
8
Clock Number
0, 1
2, 3
4, 5
6, 7
8, 9
10, 11
12, 13
14, 15
16, 17
0Ch
A23:A16
A15:A8
A7:A0
Dummy
Dummy
(D7:D0)
up to 104
MHz
A23:A16
A15:A8
A7:A0
Dummy
Dummy
Dummy (D7:D0)
up to 133
MHz
A23:A16
A15:A8
A7:A0
Dummy
Dummy
Dummy Dummy (D7:D0)
A15:A8
A7:A0
(D7:D0)
Burst Read with
Wrap
1.
7.2
up to 80
MHz
Set Read Parameter
C0h
P7:P0
Quad Page Program
33h
A23:A16
Data bytes are shifted with Most Significant Bit first. Byte fields with data in parenthesis “()” indicate data being read from the device on the IO pin.
2.
SR = Status Register. The Status Register contents and Device ID will repeat continuously until CS terminates the instruction.
3.
At least one byte of data input is required for Page Program, Quad Page Program and Program Security Register, up to 256 bytes of data input. If more
than 256 bytes of data are sent to the device, the addressing will wrap to the beginning of the page and overwrite previously sent data.
4.
See Manufacturer and Device Identification table for Device ID information.
5.
SC = Security Register.
Write Enable (06h)
Write Enable instruction is for setting the Write Enable Latch (WEL) bit in the Status Register. The WEL bit must be set prior to
every Program, Erase and Write Status Register instruction. To enter the Write Enable instruction, CS goes low prior to the
instruction “06h” into Data Input (SI) pin on the rising edge of SCK, and then driving CS high.
Figure 7-1. Write Enable Instruction for SPI Mode (left) and QPI Mode (right)
7.3
Write Enable for Volatile Status Register (50h)
This gives more flexibility to change the system configuration and memory protection schemes quickly without waiting
for the typical non-volatile bit write cycles or affecting the endurance of the Status Register non-volatile bits. To write the
volatile values into the Status Register bits, the Write Enable for Volatile Status Register (50h) instruction must be issued
prior to a Write Status Register (01h) instruction. Write Enable for Volatile Status Register instruction (Figure 7-2) will
AT25SL128A
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not set the Write Enable Latch (WEL) bit. Once Write Enable for Volatile Status Register is set, a Write Enable
instruction should not have been issued prior to setting Write Status Register instruction (01h or 31h). When Write
Enable for Volatile Status Register (50h) is set in QPI Mode, the SUS bit (S15) and Reserved bits (S13, S12, S11 and
S10) of the Status Register-2 must be driven to high after Write Status Register instruction(01h).Once Read Status
Register (05h or 31h) is issued the read values of SUS bit (S15) and Reserved bits (S13, S12, S11 and S10) of the
Status Register-2 are ignored.
Figure 7-2. Write Enable for Volatile Status Register Instruction for SPI Mode (left) and QPI Mode (right)
7.4
Write Disable (04h)
The Write Disable instruction is to reset the Write Enable Latch (WEL) bit in the Status Register. To enter the Write Disable
instruction, CS goes low prior to the instruction “04h” into Data Input (SI) pin on the rising edge of SCK, and then driving CS
high. WEL bit is automatically reset write- disable status of “0” after Power-up and upon completion of the every Program,
Erase and Write Status Register instructions.
Figure 7-3. Write Disable Instruction for SPI Mode (left) and QPI Mode (right)
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7.5
Read Status Register-1 (05h) and Read Status Register-2 (35h)
The Read Status Register instructions are to read the Status Register. The Read Status Register can be read at any
time (even in program/erase/write Status Register and Write Security Register condition). It is recommended to check
the BUSY bit before sending a new instruction when a Program, Erase, Write Status Register or Write Status Register
operation is in progress.
The instruction is entered by driving CS low and sending the instruction code “05h” for Status Register-1 or “35h” for Status
Register-2 into the SI pin on the rising edge of SCK. The status register bits are then shifted out on the SO pin at the falling
edge of SCK with most significant bit (MSB) first as shown in (Figure 7-4 and Figure 7-5). The Status Register can be read
continuously. The instruction is completed by driving CS high.
Figure 7-4. Read Status Register Instruction (SPI Mode)
Figure 7-5. Read Status Register Instruction (QPI Mode)
7.6
Write Status Register (01h)
The Write Status Register instruction is to write only non-volatile Status Register-1 bits (SRP0) and Status Register2 bits (QE and SRP1). All other Status Register bit locations are read-only and will not be affected by the Write Status
Register instruction.
A Write Enable instruction must previously have been issued prior to setting Write Status Register Instruction (Status
Register bit WEL must equal 1). Once write is enabled, the instruction is entered by driving CS low, sending the
instruction code, and then writing the status register data byte as illustrated in Figure 7-6 and Figure 7-7.
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The CS pin must be driven high after the eighth or sixteenth bit of data that is clocked in. If this is not done the Write
Status Register instruction will not be executed. If CS is driven high after the eighth clock, the QE and SRP1 bits will be
cleared to 0. After CS is driven high, the self- timed Write Status Register cycle will commence for a time duration of tw
(See AC Characteristics).
While the Write Status Register cycle is in progress, the Read Status Register instruction may still be accessed to
check the status of the BUSY bit. The BUSY bit is a 1 during the Write Status Register cycle and a 0 when the
cycle is finished and ready to accept other instructions again. When the BUSY bit is asserted, the Write Enable Latch
(WEL) bit in Status Register will be cleared to 0.
Figure 7-6. Write Status Register Instruction (SPI Mode)
Figure 7-7. Write Status Register Instruction (QPI Mode)
7.7
Write Status Register-2 (31h)
The Write Status Register-2 instruction is to write only non-volatile Status Register-2 bits (QE and SRP1).
A Write Enable instruction must previously have been issued prior to setting Write Status Register Instruction (Status
Register bit WEL must equal 1). Once write is enabled, the instruction is entered by driving CS low, sending the
instruction code, and then writing the status register data byte as illustrated in Figure 7-8 and Figure 7-9.
Using Write Status Register-2 (31h) instruction, software can individually access each one-byte status registers via different
instructions.
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Figure 7-8. Write Status Register-2 Instruction (SPI Mode)
Figure 7-9. Write Status Register-2 Instruction (QPI Mode)
7.8
Read Data (03h)
The Read Data instruction is to read data out from the device. The instruction is initiated by driving the CS pin low and then
sending the instruction code “03h” with following a 24-bit address (A23- A0) into the SI pin. After the address is received, the
data byte of the addressed memory location will be shifted out on the SO pin at the falling edge of SCK with most significant bit
(MSB) first. The address is automatically incremented to the next higher address after byte of data is shifted out allowing for a
continuous stream of data. This means that the entire memory can be accessed with a single instruction as long as the clock
continues. The instruction is completed by driving CS high. The Read Data instruction sequence is shown in Figure 7-10. If a
Read Data instruction is issued while an Erase, Program or Write Status Register cycle is in process (BUSY=1) the instruction
is ignored and will not have any effects on the current cycle. The Read Data instruction allows clock rates from D.C to a
maximum of fR (see AC Electrical Characteristics).
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Figure 7-10. Read Data Instruction
7.9
Fast Read (0Bh)
The Fast Read instruction is high speed reading mode that it can operate at the highest possible frequency of FR. The address
is latched on the rising edge of the SCK. After the 24-bit address, this is accomplished by adding “dummy” clocks as shown in
Figure 7-11. The dummy clocks means the internal circuits require time to set up the initial address. During the dummy clocks,
the data value on the SO pin is a “don’t care”. Data of each bit shifts out on the falling edge of SCK.
Figure 7-11. Fast Read Instruction (SPI Mode)
7.10
Fast Read in QPI Mode
When QPI mode is enabled, the number of dummy clock is configured by the “Set Read Parameters (C0h)” instruction to
accommodate wide range applications with different needs for either maximum Fast Read frequency or minimum data
access latency. Depending on the Read Parameter Bit P[4] and P[5] setting, the number of dummy clocks can be
configured as either 4, or 6 or 8. The default number of dummy clocks upon power up or after a Reset instruction is 4.
(Please refer to Figure 7-12, Figure 7-13 and Figure 7.11).
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Figure 7-12. Fast Read instruction (QPI Mode, 80MHz)
Figure 7-13. Fast Read instruction (QPI Mode, 104MHz)
7.11
Fast Read Dual Output (3Bh)
By using two pins (IO0 and IO1, instead of just IO0), The Fast Read Dual Output instruction allows data to be transferred from
the AT25SL128A at twice the rate of standard SPI devices. The Fast Read Dual Output instruction is ideal for quickly
downloading code from Flash to RAM upon power-up or for application that cache code-segments to RAM for execution.
The Fast Read Dual Output instruction can operate at the highest possible frequency of F R (see AC Electrical Characteristics).
After the 24-bit address, this is accomplished by adding eight “dummy” clocks as shown in Figure 7-14. The dummy clocks
allow the internal circuits additional time for setting up the initial address. During the dummy clocks, the data value on the SO
pin is a “don’t care”. However, the IO0 pin should be high-impedance prior to the falling edge of the first data out clock.
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Figure 7-14. Fast Read Dual Output instruction (SPI Mode)
7.12
Fast Read Quad Output (6Bh)
By using four pins (IO0, IO1, IO2, and IO3), The Fast Read Quad Output instruction allows data to be transferred from the
AT25SL128A at four times the rate of standard SPI devices. A Quad enable of Status Register-2 must be executed before
the device will accept the Fast Read Quad Output instruction (Status Register bit QE must equal 1).
The Fast Read Quad Output instruction can operate at the highest possible frequency of F R (see AC Electrical
Characteristics). This is accomplished by adding eight “dummy” clocks after the 24- bit address as shown in Figure 715. The dummy clocks allow the internal circuits additional time for setting up the initial address. During the dummy
clocks, the data value on the SO pin is a “don’t care”. However, the IO0 pin should be high-impedance prior to the
falling edge of the first data out clock.
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Figure 7-15. Fast Read Quad Output instruction (SPI Mode)
7.13
Fast Read Dual I/O (BBh)
The Fast Read Dual I/O instruction reduces cycle overhead through double access using two IO pins: IO0 and IO1.
Continuous read mode
The Fast Read Dual I/O instruction can further reduce cycle overhead through setting the Mode bits (M7-0) after the
input Address bits (A23-0). The upper nibble of the Mode (M7-4) controls the length of the next Fast Read Dual I/O
instruction through the inclusion or exclusion of the first byte instruction code. The lower nibble bits of the Mode (M3-0)
are don’t care (“X”), However, the IO pins should be high-impedance prior to the falling edge of the first data out clock.
If the Mode bits (M7-0) equal “Ax” hex, then the next Fast Dual I/O instruction (after CS is raised and then lowered) does
not require the instruction (BBh) code, as shown in Figure 7-16 and Figure 7-17. This reduces the instruction sequence
by eight clocks and allows the address to be immediately entered after CS is asserted low. If Mode bits (M7-0) are
any value other “Ax” hex, the next instruction (after CS is raised and then lowered) requires the first byte instruction
code, thus returning to normal operation. A Mode Bit Reset can be used to reset Mode Bits (M7-0) before issuing
normal instructions.
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Figure 7-16. Fast Read Dual I/O Instruction (initial instruction or previous M7-0 ≠ Axh)
Figure 7-17. Fast Read Dual I/O Instruction (previous M7-0 = Axh)
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7.14
Fast Read Quad I/O (EBh)
The Fast Read Quad I/O instruction reduces cycle overhead through quad access using four IO pins: IO0, IO1, IO2, and IO3.
The Quad Enable bit (QE) of Status Register-2 must be set to enable the Fast read Quad I/O Instruction.
Continuous read mode
The Fast Read Quad I/O instruction can further reduce instruction overhead through setting the Mode bits (M7-0) with
following the input Address bits (A23-0), as shown in Figure 7-18. The upper nibble of the Mode (M7-4) controls the
length of the next Fast Read Quad I/O instruction through the inclusion or exclusion of the first byte instruction code.
The lower nibble bits of the Mode (M3-0) are don’t care (“X”). However, the IO pins should be high-impedance prior to
the falling edge of the first data out clock.
If the Mode bits (M7-0) equal “Ax” hex, then the next Fast Read Quad I/O instruction (after CS is raised and then
lowered) does not require the EBh instruction code, as shown in Figure 7-19. This reduces the instruction sequence by
eight clocks and allows the address to be immediately entered after CS is asserted low. If the Mode bits (M7-0) are any
value other than “Ax” hex, the next instruction (after CS is raised and then lowered) requires the first byte instruction
code, thus retuning normal operation. A Mode Bit Reset can be used to reset Mode Bits (M7-0) before issuing normal
instructions.
Figure 7-18. Fast Read Quad I/O Instruction (Initial instruction or previous M7-0 ≠ Axh, SPI mode)
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Figure 7-19. Fast Read Quad I/O Instruction (previous M7-0 = Axh, SPI mode)
Wrap Around in SPI mode
The Fast Read Quad I/O instruction can also be used to access specific portion within a page by issuing a “Set Burst
with Wrap” (77h) instruction prior Fast Read Quad I/O (EBh) instruction. The “Set Burst with Wrap” (77h) instruction can
either enable or disable the “Wrap Around” feature for the following Fast Read Quad I/O instruction.
When “Wrap Around” is enabled, the data being accessed can be limited to an 8/16/32/64-byte section of a 256-byte
page. The output data starts at the initial address specified in the instruction, once it reaches the ending boundary of the
8/16/32/64-byte section, the output will wrap around to the beginning boundary automatically until CS is pulled high to
terminate the instruction.
The Burst with Wrap feature allows applications that use cache to quickly fetch a critical address and then fill the
cache afterwards within a fixed length (8/16/32/64-byte) of data without issuing multiple read instructions. (Please
refer to Section 7.31 Set Burst with Wrap).
Fast Read Quad I/O in QPI mode
When QPI mode in enabled, the number of dummy clocks is configured by the “Set Read Parameters (C0h)” instruction
to accommodate a wide range applications with different needs for either maximum Fast Read frequency or minimum
data access latency. Depending on the Read Parameter Bits P [4] and P [5] setting, the number of dummy clocks can
be configured as either 4 or 6 or 8. The default number of dummy clocks upon power up or after a Reset (99h)
instruction is 4.
“Continuous Read Mode” feature is also available in QPI mode for Fast Read Quad I/O instruction. In QPI mode, the
“Continuous Read Mode” bits M7-0 are also considered as dummy clocks. In the default setting, the data output will
follow the Continuous Read Mode bits immediately.
“Wrap Around” feature is not available in QPI mode for Fast Read Quad I/O instruction. To perform a read operation with
fixed data length wrap around in QPI mode, a “Burst Read with Wrap” (0Ch) instruction must be used. (Please refer to
Section 7.32 Burst Read with Wrap).
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Figure 7-20. Fast Read Quad I/O Instruction (Initial instruction or previous M7-0 ≠ Axh, QPI mode, 80 MHz)
Figure 7-21. Fast Read Quad I/O Instruction (Initial instruction or previous M7-0 ≠ Axh, QPI mode, 133 MHz)
16
17
18
19
6 Dummy Clocks
7.15
Page Program (02h)
The Page Program instruction is for programming the memory to be “0”. A Write Enable instruction must be issued
before the device accept the Page Program Instruction (Status Register bit WEL=1). After the Write Enable (WREN)
instruction has been decoded, the device sets the Write Enable Latch (WEL). The instruction is entered by driving the
CS pin low and then sending the instruction code “02h” with following a 24-bits address (A23-A0) and at least one data
byte, into the SI pin. The CS pin must be driven low for the entire time of the instruction while data is being sent to the
device. (Please refer to Figure 7-22 and Figure 7-23).
If an entire 256 byte page is to be programmed, the last address byte (the 8 least significant address bits) should be set
to 0. If the last address byte is not zero, and the number of clocks exceeds the remaining page length, the addressing
will wrap to the beginning of the page. In some cases, less than 256 bytes (a partial page) can be programmed without
having any effect on other bytes within the same page. One condition to perform a partial page program is that the
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number of clocks cannot exceed the remaining page length. If more than 256 bytes are sent to the device the addressing
will wrap to the beginning of the page and overwrite previously sent data
The CS pin must be driven high after the eighth bit of the last byte has been latched. If this is not done the Page
Program instruction will not be executed. After CS is driven high, the self-timed Page Program instruction will
commence for a time duration of tPP (See AC Characteristics). While the Page Program cycle is in progress, the Read
Status Register instruction may still be accessed for checking the status of the BUSY bit. The BUSY bit is a 1 during the
Page Program cycle and becomes a 0 when the cycle is finished and the device is ready to accept other instructions
again. When the BUSY bit is asserted, the Write Enable Latch (WEL) bit in the Status Register is cleared to 0.
Figure 7-22. Page Program Instruction (SPI Mode)
Figure 7-23. Page Program Instruction (QPI Mode)
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7.16
Quad Page Program (33h)
The Quad Page Program instruction is to program the memory as being “0” at previously erased memory areas. The Quad
Page Program takes four pins: IO0, IO1, IO2 and IO3 as address and data input, which can improve programmer performance
and the effectiveness of application of lower clock less than 5MHz. System using faster clock speed will not get more benefit for
the Quad Page Program as the required internal page program time is far more than the time data clock-in.
To use Quad Page Program, the Quad Enable bit must be set, A Write Enable instruction must be executed before the
device accepts the Quad Page Program instruction (Status Register-1, WEL = 1). The instruction is initiated by driving
the CS pin low then sending the instruction code “33h” with following a 24-bit address (A23-A0) and at least one data,
into the IO pins. The CS pin must be held low for the entire length of the instruction while data is being sent to the device.
All other functions of Quad Page Program are perfectly same as standard Page Program. (Please refer to Figure 724 and Figure 7-25).
Figure 7-24. Quad Page Program Instruction (SPI mode)
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Figure 7-25. Quad Page Program Instruction (QPI mode)
7.17
4KB Block Erase (20h)
The Block Erase instruction is to erase the data of the selected block as being “1”. The instruction is used for 4K-byte
block. Prior to the Block Erase Instruction, the Write Enable instruction must be issued. The instruction is initiated by
driving the CS pin low and shifting the instruction code “20h” followed a 24-bit block address (A23-A0). (Please refer to
Figure 7-26 and Figure 7-27). The CS pin must go high after the eighth bit of the last byte has been latched in,
otherwise, the Block Erase instruction will not be executed. After CS goes high, the self-timed Block Erase instruction will
commence for a time duration of tSE (See AC Characteristics).
While the Block Erase cycle is in progress, the Read Status Register instruction may still be accessed for checking the
status of the BUSY bit. The BUSY bit is a 1 during the Block Erase cycle and becomes a 0 when the cycle is finished
and the device is ready to accept other instructions again. When the BUSY bit is asserted, the Write Enable Latch (WEL)
bit in the Status Register is cleared to 0.
Figure 7-26. Block Erase Instruction (SPI Mode)
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Figure 7-27. Block Erase Instruction (QPI Mode)
7.18
32KB Block Erase (52h)
The Block Erase instruction is to erase the data of the selected block as being “1”. The instruction is used for 32K-byte
Block erase operation. Prior to the Block Erase Instruction, a Write Enable instruction must be issued. The instruction is
initiated by driving the CS pin low and shifting the instruction code “52h” followed a 24-bit block address (A23-A0).
(Please refer to Figure 7-28 and Figure 7-29). The CS pin must go high after the eighth bit of the last byte has been
latched in, otherwise, the Block Erase instruction will not be executed. After CS is driven high, the self-timed Block Erase
instruction will commence for a time duration of tBE1 (See AC Characteristics).
While the Block Erase cycle is in progress, the Read Status Register instruction may still be read the status of the
BUSY bit. The BUSY bit is a 1 during the Block Erase cycle and becomes a 0 when the cycle is finished and the
device is ready to accept other instructions again. When the BUSY bit is asserted, the Write Enable Latch (WEL) bit in
the Status Register is cleared to 0.
Figure 7-28. 32KB Block Erase Instruction (SPI Mode)
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Figure 7-29. 32KB Block Erase Instruction (QPI Mode)
7.19
64KB Block Erase (D8h)
The Block Erase instruction is to erase the data of the selected block as being “1”. The instruction is used for 64K-byte
Block erase operation. Prior to the Block Erase Instruction, a Write Enable instruction must be issued. The instruction is
initiated by driving the CS pin low and shifting the instruction code “D8h” followed a 24-bit block address (A23-A0).
(Please refer to Figure 7-30 and Figure 7-31). The CS pin must go high after the eighth bit of the last byte has been
latched in, otherwise, the Block Erase instruction will not be executed. After CS is driven high, the self-timed Block Erase
instruction will commence for a time duration of tBE2 (See AC Characteristics).
While the Block Erase cycle is in progress, the Read Status Register instruction may still be read the status of the
BUSY bit. The BUSY bit is a 1 during the Block Erase cycle and becomes a 0 when the cycle is finished and the
device is ready to accept other instructions again. When the BUSY bit is asserted, the Write Enable Latch (WEL) bit in
the Status Register is cleared to 0.
Figure 7-30. 64KB Block Erase Instruction (SPI Mode)
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Figure 7-31. 64KB Block Erase Instruction (QPI Mode)
7.20
Chip Erase (C7h / 60h)
The Chip Erase instruction clears all bits in the device to be FFh (all 1s). Prior to the Chip Erase Instruction, a Write
Enable instruction must be issued. The instruction is initiated by driving the CS pin low and shifting the instruction code
“C7h” or “60h”. (Please refer to Figure 7-32). The CS pin must go high after the eighth bit of the last byte has been
latched in, otherwise, the Chip Erase instruction will not be executed. After CS is driven high, the self-timed Chip Erase
instruction will commence for a duration of tCE (See AC Characteristics).
While the Chip Erase cycle is in progress, the Read Status Register instruction may still be accessed to check the status
of the BUSY bit. The BUSY bit is a 1 during the Chip Erase cycle and becomes a 0 when the cycle is finished and the
device is ready to accept other instructions again. When the BUSY bit is asserted, the Write Enable Latch (W EL) bit in
the Status Register is cleared to 0.
Figure 7-32. Chip Erase Instruction for SPI Mode (left) and QPI Mode (right)
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7.21
Erase / Program Suspend (75h)
The Erase/Program Suspend instruction allows the system to interrupt a Block Erase, Block Erase operation or a
Page Program, Quad Data Input Page Program, Quad Page Program operation.
Erase Suspend is valid only during the Block or Block erase operation. The Write Status Register-1 (01h), Write Status
Register-2 (31h) instruction and Erase instructions (20h, 52h, D8h, C7h, 60h) are not allowed during Erase Suspend.
During the Chip Erase operation, the Erase Suspend instruction is ignored.
Program Suspend is valid only during the Page Program, Quad Data Input Page Program or Quad Page Program
operation. The Write Status Register-1 (01h), Write Status Register-2 (31h) instruction, Program instructions (02h and
33h) and Erase Instructions (20h, 52h, D8h, C7h, 60h) are not allowed during Program Suspend.
The Erase/Program Suspend instruction “75h” will be accepted by the device only if the SUS bit in the Status Register
equals to 0 and the BUSY bit equals to 1 while a Block Erase or a Page Program operation is on-going. If the SUS bit
equals to 1 or the BUSY bit equals to 0, the Suspend instruction will be ignored by the device. A maximum of time of
“tSUS” (See AC Characteristics) is required to suspend the erase or program operation. After Erase/Program Suspend,
the SUS bit in the Status Register will be set from 0 to 1 immediately and The BUSY bit in the Status Register will be
cleared from 1 to 0 within “tSUS”. For a previously resumed Erase/Program operation, it is also required that the
Suspend instruction “75h” is not issued earlier than a minimum of time of “tSUS” following the preceding Resume
instruction “7Ah”.
Unexpected power- off during the Erase/Program suspend state will reset the device and release the suspend state.
SUS bit in the Status Register will also reset to 0. The data within the page, or block that was being suspended may
become corrupted. It is recommended for the user to implement system design techniques against the accidental
power interruption and preserve data integrity during erase/program suspend state. (Please refer to Figure 7-33 and
Figure 7-34).
Figure 7-33. Erase Suspend instruction (SPI Mode)
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Figure 7-34. Erase Suspend instruction (QPI Mode)
7.22
Erase / Program Resume (7Ah)
The Erase/Program Resume instruction “7Ah” is to restart the Block Erase operation or the Page Program operation
upon an Erase/Program Suspend. The Resume instruction “7Ah” will be accepted by the device only if the SUS bit in
the Status Register equals to 1 and the BUSY bit equals to 0. After issued, hardware clears the SUS bit from 1 to 0
immediately, and sets the BUSY bit from 0 to 1 within 200ns and the Block completes either the erase operation, or the
page completes the program operation. If the SUS bit equals to 0 or the BUSY bit equals to 1, the Resume instruction
“7Ah” will be ignored by the device.
Resume instruction cannot be accepted if the previous Erase/Program Suspend operation was interrupted by
unexpected power-off. It is also required that a subsequent Erase/Program Suspend instruction not to be issued within a
minimum of time of “tSUS” following a previous Resume instruction. (Please refer to Figure 7-35 and Figure 7-36).
Figure 7-35. Erase / Program Resume instruction (SPI Mode)
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Figure 7-36. Erase / Program Resume instruction (QPI Mode)
7.23
Deep Power Down (B9h)
Executing the Deep Power Down instruction is the best way to put the device in the lowest power consumption. The
Deep Power Down instruction reduces the standby current (from ICC1 to ICC2, as specified in AC characteristics). The
instruction is entered by driving the CS pin low with following the instruction code “B9h”. (Please refer to Figure 7-37 and
Figure 7-38).
The CS pin must go high exactly at the byte boundary (the latest eighth bit of instruction code been latched-in);
otherwise, the Deep Power Down instruction is not executed. After CS goes high, it requires a delay of tDP and the Deep
Power Down mode is entered. While in the Release Deep Power Down / Device ID instruction, which restores the device
to normal operation, will be recognized. All other instructions are ignored including the Read Status Register instruction,
which is always available during normal operation. Deep Power Down Mode automatically stops at Power-Down, and the
device always Power-up in the Standby Mode.
Figure 7-37. Deep Power Down Instruction (SPI Mode)
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Figure 7-38. Deep Power Down Instruction (QPI Mode)
7.24
Release Deep Power Down / Device ID (ABh)
The Release Deep Power Down / Device ID instruction is a multi-purpose instruction. It can be used to release the
device from the Deep Power Down state or obtain the device identification (ID).
The instruction is issued by driving the CS pin low, sending the instruction code “ABh” and driving CS high as shown in
figure Figure 7-39 and Figure 7-40. Release from Deep Power Down require the time duration of tRES1 (See AC
Characteristics) for re-work a normal operation and accepting other instructions. The CS pin must keep high during the
tRES1 time duration.
The Device ID can be read during SPI mode only. In other words, Device ID feature is not available in QPI mode for Release
Deep Power Down/Device ID instruction. To obtain the Device ID in SPI mode, instruction is initiated by driving the CS pin
low and sending the instruction code “ABh” with following 3-dummy bytes. The Device ID bits are then shifted on the
falling edge of SCK with most significant bit (MSB) first as shown in Figure 7-41. After CS is driven high it must keep
high for a time duration of tRES2 (See AC Characteristics). The Device ID can be read continuously. The instruction is
completed by driving CS high.
If the Release from Deep Power Down /Device ID instruction is issued while an Erase, Program or Write cycle is in process
(when BUSY equals 1) the instruction is ignored and will not have any effects on the current cycle.
Figure 7-39. Release Power Down Instruction (SPI Mode)
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Figure 7-40. Release Power Down Instruction (QPI Mode)
Figure 7-41. Release Power Down / Device ID Instruction (SPI Mode)
7.25
Read Manufacturer / Device ID Dual I/O (90h)
The Read Manufacturer/ Device ID Dual I/O instruction provides both the JEDEC assigned manufacturer ID and the
specific device ID.
The Read Manufacturer/ Device ID instruction is very similar to the Fast Read Dual I/O instruction. The instruction is
initiated by driving the CS pin low and shifting the instruction code “90h” followed by a 24-bit address (A23-A0) of
000000h. After which, the Manufacturer ID for Adesto (1Fh) and the Device ID(17h) are shifted out on the falling edge of
SCK with most significant bit (MSB) first as shown in Figure 7-42 and Figure 7-43. If the 24-bit address is initially set to
000001h the Device ID will be read first and then followed by the Manufacturer ID. The Manufacturer and Device ID can
be read continuously, alternating from one to the other. The instruction is completed by driving CS high.
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Figure 7-42. Read Manufacturer/ Device ID instruction (SPI Mode)
Figure 7-43. Read Manufacturer/ Device ID instruction (QPI Mode)
7.26
Read Manufacturer / Device ID Dual I/O (92h)
The Read Manufacturer/ Device ID Dual I/O instruction provides both the JEDEC assigned manufacturer ID and the
specific device ID.
The Read Manufacturer/ Device ID instruction is very similar to the Fast Read Dual I/O instruction. The instruction is
initiated by driving the CS pin low and shifting the instruction code “92h” followed by a 24-bit address (A23-A0) of
000000h. After which, the Manufacturer ID for Adesto (1Fh) and the Device ID (17h) are shifted out on the falling edge of
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SCK with most significant bit (MSB) first as shown in Figure 7-44. If the 24-bit address is initially set to 000001h the
Device ID will be read first and then followed by the Manufacturer ID. The Manufacturer and Device ID can be read
continuously, alternating from one to the other. The instruction is completed by driving CS high.
Figure 7-44. Read Dual Manufacturer/ Device ID Dual I/O instruction (SPI Mode)
7.27
Read Manufacturer / Device ID Quad I/O (94h)
The Read Manufacturer/ Device ID Quad I/O instruction provides both the JEDEC assigned manufacturer ID and the
specific device ID.
The Read Manufacturer/ Device ID instruction is very similar to the Fast Read Quad I/O instruction. The instruction is
initiated by driving the CS pin low and shifting the instruction code “94h” followed by a 24-bit address (A23-A0) of
000000h. After which, the Manufacturer ID for Adesto (1Fh) and the Device ID (17h) are shifted out on the falling edge of
SCK with most significant bit (MSB) first as shown in Figure 7-45. If the 24-bit address is initially set to 000001h the
Device ID will be read first and then followed by the Manufacturer ID. The Manufacturer and Device ID can be read
continuously, alternating from one to the other. The instruction is completed by driving CS high.
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Figure 7-45. Read Quad Manufacturer/ Device ID Quad I/O instruction (SPI Mode)
JEDEC ID (9Fh)
For compatibility reasons, the AT25SL128A provides several instructions to electronically determine the identity of the
device. The Read JEDEC ID instruction is congruous with the JEDEC standard for SPI compatible serial flash memories
that was adopted in 2003. The instruction is entered by driving the CS pin low with following the instruction code “9Fh”.
JEDEC assigned Manufacturer ID byte for Adesto (1Fh) and two Device ID bytes, Memory Type (ID-15-ID8) and
Capacity (ID7-ID0) are then shifted out on the falling edge of SCK with most significant bit (MSB) first shown in Figure
7-46 and Figure 7-47. For memory type and capacity values refer to Manufacturer and Device Identification table. The
JEDEC ID can be read continuously. The instruction is terminated by driving CS high.
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Figure 7-46. Read JEDEC ID instruction (SPI Mode)
Figure 7-47. Read JEDEC ID instruction (QPI Mode)
7.28
Enable QPI (38h)
The AT25SL128A support both Standard/Dual/Quad Serial Peripheral interface (SPI) and Quad Peripheral Interface
(QPI). However, SPI mode and QPI mode cannot be used at the same time. Enable QPI instruction is the only way to
switch the device from SPI mode to QPI mode.
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In order to switch the device to QPI mode, the Quad Enable (QE) bit in Status Register 2 must be set to 1 first, and an
Enable QPI instruction must be issued. If the Quad Enable (QE) bit is 0, the Enable QPI instruction will be ignored and
the device will remain in SPI mode.
After power-up, the default state of the device is SPI mode. See the instruction Set Table 7.2 for all the commands
supported in SPI mode and the instruction Set Table 7-5 for all the instructions supported in QPI mode.
When the device is switched from SPI mode to QPI mode, the existing Write Enable and Program/Erase Suspend status,
and the Wrap Length setting will remain unchanged.
Figure 7-48. Enable QPI instruction (SPI Mode only)
7.29
Disable QPI (FFh)
By issuing Disable QPI (FFh) instruction, the device is reset SPI mode. When the device is switched from QPI mode to
SPI mode, the existing Write Enable Latch (WEL) and Program/Erase Suspend status, and the Wrap Length setting will
remain unchanged.
Figure 7-49. Disable QPI instruction for QPI mode
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7.30
Word Read Quad I/O (E7h)
The Quad I/O dramatically reduces instruction overhead allowing faster random access for code execution (XIP) directly
from the Quad SPI. The Quad Enable bit (QE) of Status Register-2 must be set to enable the Word Read Quad I/O
instruction. The lowest Address bit (A0) must equal 0 and only two dummy clocks are required prior to the data output.
Continuous Read Mode
The Word Read Quad I/O instruction can further reduce instruction overhead through setting the “Continuous Read
Mode” bits (M7-0) after the input Address bits (A23-0), as shown in Figure 7-50. The upper nibble of the (M7-4)
controls the length of the next Word Read Quad I/O instruction through the inclusion or exclusion of the first byte
instruction code. The lower nibble bits of the (M[3:0]) are don’t care (“X”). However, the IO pins should be highimpedance prior to the falling edge of the first data out clock.
If the “Continuous Read Mode” bits M[7-4] = Ah, then the next Fast Read Quad I/O instruction (after CS is raised and
then lowered) does not require the E7h instruction code, as shown in Figure 7-51. This reduces the instruction sequence
by eight clocks and allows the Read address to be immediately entered after CS is asserted low. If the “Continuous
Read Mode” bits M[7:4] do not equal Ah (1010), the next instruction (after CS is raised and then lowered) requires the
first byte instruction code, thus returning to normal operation.
Figure 7-50. Word Read Quad I/O instruction (Initial instruction or previous set M7-0 ≠ Axh, SPI Mode)
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Figure 7-51. Word Read Quad I/O instruction (Previous instruction set M7-0 = Axh, SPI Mode)
Wrap Around in SPI mode
The Word Read Quad I/O instruction can also be used to access a specific portion within a page by issuing a “Set
Burst with Wrap” (77h) instruction prior to E7h. The “Set Burst with Wrap” (77h) instruction can either enable or disable
the “Wrap Around” feature for the following E7h commands. When “Wrap Around” is enabled, the output data starts at
the initial address specified in the instruction, once it reaches the ending boundary of the 8/16/32/64-byte section,
the output will wrap around to the beginning boundary automatically until CS is pulled high to terminate the instruction.
The Burst with Wrap feature allows applications that use cache to quickly fetch a critical address and then fill the cache
afterwards within a fixed length (8/16/32/64-byte) of data without issuing read instructions.
The “Set Burst with Wrap” instruction allows three “Wrap Bits”, W6-4 to be set. The W4 bit is used to enable or disable
the “Wrap Around” operation while W6-5 is used to specify the length of the wrap around section within a page.
7.31
Set Burst with Wrap (77h)
The Set Burst with Wrap (77h) instruction is used in conjunction with “Fast Read Quad I/O” and “Word Read Quad
I/O” instructions to access a fixed length of 8/16/32/64-byte section within a 256-byte page. Certain applications can
benefit from this feature and improve the overall system code execution performance. Before the device will accept the
Set Burst with Wrap instruction, a Quad enable of Status Register-2 must be executed (Status Register bit QE must
equal 1).
The Set Burst with Wrap instruction is initiated by driving the CS pin low and then shifting the instruction code “77h”
followed by 24 dummy bits and 8 “Wrap Bits”, W7-0. The instruction sequence is shown in Set Burst with Wrap
Instruction Sequence. Wrap bit W7 and W3-0 are not used.
Table 7-6.
Encoding of W[6:4] Bits
W4 = 0
W4 = 1 (Default)
W6, W5
Wrap Around
Wrap Length
Wrap Around
Wrap Length
00
Yes
8-byte
No
N/A
01
Yes
16-byte
No
N/A
10
Yes
32-byte
No
N/A
11
Yes
64-byte
No
N/A
Once W6-4 is set by a Set Burst with Wrap instruction, all the following “Fast Read Quad I/O” and Word Read Quad I/O
instructions will use the W6-4 setting to access the 8/16/32/64-byte section within any page. To exit the “Wrap Around” function
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and return to normal read operation, another Set Burst with Wrap instruction should be issued to set W4 = 1. The default
value of W4 upon power on is 1. In the case of a system Reset while W4 = 0, it is recommended that the controller issues a
Set Burst with Wrap instruction or Reset (99h) instruction to reset W4 = 1 prior to any normal Read instructions since
AT25SL128A does not have a hardware Reset Pin.
Figure 7-52. Set Burst with Wrap Instruction Sequence
7.32
Burst Read with Wrap (0Ch)
The “Burst Read with Wrap (0Ch)” instruction provides an alternative way to perform the read operation with “Wrap
Around” in QPI mode. The instruction is similar to the “Fast Read (0Bh)” instruction in QPI mode, except the
addressing of the read operation will “Wrap Around” to the beginning boundary of the “Wrap Length” once the ending
boundary is reached.
The “Wrap Length” and the number of dummy of clocks can be configured by the “Set Read Parameters (C0h)”
instruction.
Figure 7-53. Burst Read with Wrap instruction (QPI Mode, 80MHz)
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Figure 7-54. Burst Read with Wrap instruction (QPI Mode, 133 MHz)
16
17
18
19
8 Dummy Clocks
7.33
Set Read Parameters (C0h)
In QPI mode, to accommodate a wide range of applications with different needs for either maximum read frequency or
minimum data access latency, “Set Read Parameters (C0h)” instruction can be used to configure the number of
dummy clocks for “Fast Read (0Bh)”, “Fast Read Quad I/O (EBh)” and “Burst Read with Wrap (0Ch)” instructions, and
to configure the number of bytes of “Wrap Length” for the “Burst Read with Wrap (0Ch)” instruction.
In Standard SPI mode, the “Set Read Parameters (C0h)” instruction is not accepted. The dummy clocks for various Fast
Read instructions in Standard/Dual/Quad SPI mode are fixed, please refer to the instruction. and for details Table 7.2,
Table 7-3, Table 7-4, and Table 7-5. The “Wrap Length” is set by W6-5 bit in the “Set Burst with Wrap (77h)” instruction.
This setting will remain unchanged when the device is switched from Standard SPI mode to QPI mode.
The default “Wrap Length” after a power up or a Reset instruction is 8 bytes, the default number of dummy clocks is 4.
Table 7-7.
Encoding of P[5:4] Bits
P5, P4
Dummy
Clocks
Maximum
Read Frequency
00
4
80 MHz
01
4
80 MHz
10
6
104 MHz
11
8
133 MHz
Table 7-8.
Encoding of P[1:0] Bits
P1, P0
Wrap Length
00
8-byte
01
16-byte
10
32-byte
11
64-byte
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Figure 7-55. Set Read Parameters instruction (QPI Mode)
7.34
Enable Reset (66h) and Reset (99h)
For eight-pin packages, the AT25SL128A provide a software Reset instruction instead of a dedicated RESET pin.
Once the Reset instruction is accepted, any on-going internal operations will be terminated and the device will return to
its default power-on state and lose all the current volatile settings, such as Volatile Status Register bits, Write Enable
Latch (WEL) status, Program/Erase Suspend status, Continuous Read Mode bit setting, Read parameter setting and
Wrap bit setting.
“Enable Reset (66h)” and “Reset (99h)” instructions can be issued in either SPI mode or QPI mode. To avoid accidental
reset, both instructions must be issued in sequence. Any other instructions other than “Reset (99h)” after the “Enable
(66h)” instruction will disable the “Reset Enable” state. A new sequence of “Enable Reset (66h)” and “Reset (99h)” is
needed to reset the device. Once the Reset instruction is accepted by the device will take approximately tRST = 30us
to reset. During this period, no instruction will be accepted.
Data corruption may happen if there is an on-going or suspended internal Erase or Program operation when Reset
instruction sequence is accepted by device. It is recommended to check the BUSY bit and the SUS bit in Status Register
before issuing the Reset instruction sequence.
Figure 7-56. Enable Reset and Reset Instruction (SPI Mode)
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Figure 7-57. Enable Reset and Reset Instruction (QPI Mode)
7.35
Read Serial Flash Discovery Parameter (5Ah)
The Read Serial Flash Discovery Parameter (SFDP) instruction allows reading the Serial Flash Discovery Parameter
area (SFDP). This SFDP area is composed of 2048 read-only bytes containing operating characteristics and vendor
specific information. The SFDP area is factory programmed. If the SFDP area is blank, the device is shipped with all the
SFDP bytes at FFh. If only a portion of the SFDP area is written to, the portion not used is shipped with bytes in erased
state (FFh). The instruction sequence for the read SFDP has the same structure as that of a Fast Read instruction. First,
the device is selected by driving Chip Select (CS) Low. Next, the 8-bit instruction code (5Ah) and the 24-bit address
are shifted in, followed by 8 dummy clock cycles. The bytes of SFDP content are shifted out on the Serial Data Output
(SO) starting from the specified address. Each bit is shifted out during the falling edge of Serial Clock (SCK). The
instruction sequence is shown here. The Read SFDP instruction is terminated by driving Chip Select (CS) High at any
time during data output.
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Figure 7-58. Read SFDP Register Instruction
Table 7-9.
SFDP Signature and Headers
Description
Comment
SFDP Signature
Address
Byte
Bits
Data (binary)
Data (hex)
00h
07:00
0101 0011
53h
01h
15:08
0100 0110
46h
02h
23:16
0100 0100
44h
03h
31:24
0101 0110
50h
SFDP Minor Revision
Start from 00h
04h
07:00
0000 0110
06h
SFDP Major Revision
Start from 01h
05h
15:08
0000 0001
01h
Number of Parameters
Headers
Start from 00h
06h
23:16
0000 0001
01h
Reserved
FFh
07h
31:24
1111 1111
FFh
JEDEC Parameter ID (LSB)
JEDEC Parameter ID
(LSB) = 00h
08h
07:00
0000 0000
00h
Parameter Table Minor
Revision
Start from 00h
09h
15:08
0000 0110
06h
Parameter Table Major
Start from 01h
0Ah
23:16
0000 0001
01h
0Bh
31:24
0001 0000
10h
Revision
Parameter Table Length
(double words)
How many DWORDs in
the parameter table
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Table 7-9.
SFDP Signature and Headers (Continued)
Description
Comment
Parameter Table Pointer
Address of Adesto
Parameter Table
Address
Byte
Bits
Data (binary)
Data (hex)
0Ch
07:00
0011 0000
30h
0Dh
15:08
0000 0000
00h
0Eh
23:16
0000 0000
00h
JEDEC Parameter ID (MSB)
JEDEC Parameter ID
(MSB):FFh
0Fh
31:24
1111 1111
FFh
JEDEC Parameter ID (LSB)
Adesto Manufacturer ID
10h
07:00
0001 1111
1Fh
Parameter Table
Minor Revision
Start from 00h
11h
15:08
0000 0000
00h
Parameter Table
Major Revision
Start from 01h
12h
23:16
0000 0001
01h
Parameter Table Length
(double words)
How many DWORDs in
the parameter table
13h
31:24
0000 0010
02h
Parameter Table
Pointer (PTP)
Address of Adesto
Parameter Table
14h
07:00
1000 0000
80h
15h
15:08
0000 0000
00h
16h
23:16
0000 0000
00h
17h
31:24
0000 0001
01h
Reserved
Table 7-10.
FFh
SFDP Parameters Table 1
Description
Erase Granularity
Comment
Address
Byte
Bits
Data
(binary)
Data (hex)
01: 4KB available
30h
01:00
01
E5h
11: 4KB not available
Write Granularity
0: 1 Byte
1: 64 bytes or larger
02
1
Volatile Status Register Block
Protect Bits
0: Nonvolatile status bit
1: Volatile status bit
03
0
Volatile Status Register Write
Enable Opcode
0: 50h Opcode to enable,
if bit 3 = 1
04
0
07:05
111
15:08
0010 0000
Reserved
4KB Erase Opccde
Opcode or FFh
31h
20h
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Table 7-10.
SFDP Parameters Table 1 (Continued)
Description
Comment
Fast Dual Read Output
(1 -1 -2)
0: Not supported,
1: Supported
Number of Address Bytes
00: 3 Byte only
Address
Byte
Bits
Data
(binary)
Data (hex)
32h
16
1
F1h
18:17
00
01: 3 or 4 Byte
10: 4 Byte only
11: Reserved
Double Transfer Rate (DTR)
Clocking
0: Not supported,
1: Supported
19
0
Fast Dual I/O Read
(1-2- 2)
0: Not supported,
1: Supported
20
1
Fast Quad I/O Read
(1-4-4)
0: Not supported,
1: Supported
21
1
Fast Quad Output Read
(1-1-4)
0: Not supported,
1: Supported
22
1
Reserved
FFh
23
1
Reserved
FFh
33h
31:24
1111 1111
FFh
34h
07:00
1111 1111
FFh
35h
15:08
1111 1111
FFh
36h
23:16
1111 1111
FFh
37h
31:24
0000 0111
07h
38h
04:00
00100
44h
07:05
010
Flash Memory Density
Fast Quad I/O (1-4-4)
Number of dummy clocks
Number of dummy clocks
Fast Quad I/O (1-4-4)
Number of mode bits
Number of mode bits
Fast Quad I/O (1-4-4) Read
Opcode
Opcode or FFh
39h
15:08
1110 1011
EBh
Fast Quad Output (1-1-4)
Number of dummy clocks
Number of dummy clocks
3Ah
20:16
01000
08h
Fast Quad Output (1-1-4)
Number of mode bits
Number of mode bits
23:21
000
Fast Quad Output (1-1-4)
Read Opcode
Opcode or FFh
3Bh
31:24
0110 1011
6Bh
Fast Dual Output (1-1-2)
Number of dummy clocks
Number of dummy clocks
3Ch
04:00
01000
08h
Fast Dual Output (1-1-2)
Number of mode bits
Number of mode bits
07:05
000
Fast Dual Output (1-1-2)
Read Opcode
Opcode or FFh
15:08
0011 1011
3Dh
3Bh
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Table 7-10.
SFDP Parameters Table 1 (Continued)
Description
Comment
Address
Byte
Bits
Data
(binary)
Data (hex)
Fast Dual I/O (1-2-2)
Number of dummy clocks
Number of dummy clocks
3Eh
20:16
00000
80h
Fast Dual I/O (1-2-2)
Number of mode bits
Number of mode bits
23:21
100
Fast Dual I/O (1-2-2)
Read Opcode
Opcode or FFh
3Fh
31:24
1011 1011
BBh
Fast Dual DPI (2-2-2)
0: Not supported,
1: Supported
40h
0
0
FEh
Reserved
FFh
03:01
111
Fast Quad QPI (4-4-4)
0: Not supported,
1: Supported
04
1
Reserved
FFh
07:05
111
Reserved
FFh
41h
15:08
1111 1111
FFh
Reserved
FFh
42h
23:16
1111 1111
FFh
Reserved
FFh
43h
31:24
1111 1111
FFh
Reserved
FFh
44h
07:00
1111 1111
FFh
Reserved
FFh
45h
15:08
1111 1111
FFh
Fast Dual DPI (2-2-2)
Number of dummy clocks
Number of dummy clocks
46h
20:16
0 0000
00h
Fast Dual DPI (2-2-2)
Number of mode bits
Number of mode bits
23:21
000
Fast Dual DPI(2-2-2)
Opcode or FFh
47h
31:24
1111 1111
FFh
Reserved
FFh
48h
07:00
1111 1111
FFh
Reserved
FFh
49h
15:08
1111 1111
FFh
Fast Quad QPI (4-4-4)
Number of dummy clocks
Number of dummy clocks
4Ah
20:16
00010
42h
Fast Quadl QPI (4-4-4)
Number of mode bits
Number of mode bits
23:21
010
Fast Quad QPI(4-4-4)
Opcode or FFh
4Bh
31:24
1110 1011
EBh
Erase type-1 Size
4KB = 2^0Ch, 32KB = 2^0Fh,
64KB = 2^10h; (2^Nbyte)
4Ch
07:00
0000 1100
0Ch
Erase type-1 Opcode
Opcode or FFh
4Dh
15:08
0010 0000
20h
Erase type-2 Size
4KB = 2^0Ch, 32KB = 2^0Fh,
64KB = 2^10h; (2^Nbyte)
4Eh
23:16
0000 1111
0Fh
Erase type-2 Opcode
Opcode or FFh
4Fh
31:24
0101 0010
52h
Read Opcode
Read Opcode
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Table 7-10.
SFDP Parameters Table 1 (Continued)
Address
Byte
Bits
Data
(binary)
Data (hex)
4KB = 2^0Ch, 32KB = 2^0Fh,
64KB = 2^10h; (2^Nbyte)
50h
07:00
0001 0000
10h
Erase Type-3 Opcode
Opcode or FFh
51h
15:08
1101 1000
D8h
Erase Type-4 Size
4KB = 2^0Ch, 32KB = 2^0Fh,
64KB = 2^10h; (2^Nbyte)
52h
23:16
0000 0000
00h
Erase Type-4 Opcode
Opcode or FFh
53h
31:24
1111 1111
FFh
Erase Maximum/Typical
Ratio
Maximum = 2 * (COUNT + 1) *
Typical
03:00
0011
Erase type-1 Typical time
Count or 00h
54h
55h
56h
57h
08:04
0 0011
33h
62h
D5h
00h
Erase type-1 Typical units
00b: 1ms
01b: 16ms
10b: 128ms
11b: 1s
10:09
01
Erase type-2 Typical time
Count or 00h
15:11
0110 0
Erase type-2 Typical units
00b: 1ms
01b: 16ms
10b: 128ms
11b: 1s
17:16
01
Erase type-3 Typical time
Count or 00h
22:18
101 01
Erase type-3 Typical units
00b: 1ms
01b: 16ms
10b: 128ms
11b: 1s
24:23
01
Erase type-4 Typical time
Count or 00h
29:25
00 000
Erase type-4 Typical units
00b: 1ms
01b: 16ms
10b: 128ms
11b: 1s
31:30
00
Program Maximum/Typical
Ratio
Maximum = 2 * (COUNT + 1) *
Typical
03:00
0100
Page Size
2^N bytes
07:04
1000
Description
Comment
Erase Type-3 Size
58h
84h
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Table 7-10.
SFDP Parameters Table 1 (Continued)
Bits
Data
(binary)
12:08
0 1001
13
1
Count or 00h
17:14
01 00
Program Byte Typical units,
1st byte
0: 1µs, 1: 8µs
18
0
Program Additional Byte
Typical time
Count or 00h
22:19
000 0
Program Additional Byte
Typical units
0: 1µs, 1: 8µs
23
0
Erase Chip Typical time
Count or 00h
28:24
0 1110
Erase Chip Typical units
00b: 16ms
01b: 256ms
10b: 4s
11b: 64s
30:29
10
Reserved
1h
31
1
Prohibited Op during
Program Suspend
See datasheet
03:00
11010
Prohibited Op during Erase
Suspend
See datasheet
07:04
1110
Reserved
1h
08
1
Program Resume to
Suspend time
Count of 64µs
12:09
0 000
Program Suspend Maximum
time
Count or 00h
17:13
11 101
Program Suspend Maximum
units
00b: 128ns,
01b: 1µs,
10b: 8µs,
11b: 64µs
19:18
01
Erase Resume to Suspend
time
Count of 64µs
23:20
0000
Erase Suspend Maximum
time
Count or 00h
28:24
1 1101
Erase Suspend Maximum
units
00b: 128ns,
01b: 1µs,
10b: 8µs,
11b: 64µs
30:29
01
Suspend / Resume
supported
0: Program and Erase suspend
supported
1: not supported
31
0
Program Resume Opcode
Opcode or FFh
7:0
0111 1010
Description
Comment
Program Page Typical time
Count or 00h
Program Page Typical units
0: 8µs, 1: 64µs
Program Byte Typical time,
1st byte
Address
Byte
59h
5Ah
5Bh
5Ch
5Dh
5Eh
5Fh
60h
Data (hex)
29h
01h
CEh
ECh
A1h
07h
3Dh
7Ah
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Table 7-10.
SFDP Parameters Table 1 (Continued)
Description
Comment
Address
Byte
Bits
Data
(binary)
Data (hex)
Program Suspend Opcode
Opcode or FFh
61h
15:8
0111 0101
75h
Resume Opcode
Opcode or FFh
62h
23:16
0111 1010
7Ah
Suspend Opcode
Opcode or FFh
63h
31:24
0111 0101
75h
Reserved
11b
64h
01:00
11
F7h
Status Register Busy Polling
xxxxx1b: Opcode = 05h,
bit 0 = 1 Busy,
xxxx1xb: Opcode = 70h,
bit 7 = 0 Busy,
Others: reserved
07:02
1111 01
Exit Deep Power-down time
Count or 00h
12:08
0 0010
Exit Deep Power-down units
00b: 128ns,
01b: 1µs,
10b: 8µs,
11b: 64µs
14:13
01
Exit Deep Power-down
Opcode
Opcode or FFh
22:15
101 0101 1
Enter Deep Power-down
Opcode
Opcode or FFh
30:23
101 1100 1
Deep Power-down
Supported
0: Deep Power-down supported,
1: not supported
31
0
03:00
1001
08:04
0 0001
09
1
Fast Quad I/O Continuous
(0-4-4) Exit
15:10
1111 01
Fast Quad I/O Continuous
(0-4-4) Enter
19:16
1100
Quad Enable Requirements
(QER)
22:20
001
23
0
6Bh
31;24
1111 1111
FFh
6Ch
06:00
110 1000
E8h
07
1
Disable 4-4-4 Read Mode
68h
69h
6Ah
Enable 4-4-4 Read Mode
Fast Quad I/O Continuous
(0-4-4) supported
0: not supported,
1: Quad I/O 0-4-4 supported
HOLD or RESET Disable
0: not supported,
1: use Configuration
register bit 4
Reserved
FFh
Status Register Opcode
Reserved
65h
66h
67h
1h
A2h
D5h
5Ch
19h
F6h
1Ch
Soft Reset Opcodes
6Dh
13:08
01 0000
4-Byte Address Exit
6Eh
23:14
1100 0000 00
4-Byte Address Enter
6Fh
31:24
1000 0000
10h
C0h
80h
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Table 7-11.
SFDP Parameters Table 2
Address
(h) Byte
Data (b)
(Bit)
Data (h)
(Byte)
15:0
0000 0000
0001 0111
00h
17h
82h/83h
31:16
0000 0000
0010 0000
00h
20h
84h
85h
01:00
00
00h
00h
0: power up unprotected
1: power up protected
02
0
Protection Disable Opcodes
011b: use status register
05:03
000
Protection Enable Opcodes
011b: use status register
08:06
0 00
Protection Read Opcodes
011b: use status register
11:09
000
Protection Register Erase
Opcode
00b: not supported,
01b: Opcodes 3Dh, 2Ah,
7Fh, CFh,
13:12
00
Protection Register Program
Opcode
00b: not supported
01b: Opcodes 3Dh, 2Ah,
7Fh, FCh
15:14
00
Description
Comment
VCC Minimum Voltage
1650h: 1.65V,
1700h: 1.70V,
2300h: 2.30V,
2500h: 2.50V,
2700h: 2.70V
80h
81h
VCC Maximum Voltage
1950h: 1.95V,
3600h: 3.60V,
4000h: 4.00V,
4400h: 4.40V
Array Protection Method
10b: use non-volatile
status register
Power up Protection default
Bits
Reserved
FFh
86h
23:16
1111 1111
FFh
Reserved
FFh
87h
31:24
1111 1111
FFh
Reserved
FFh
88h - FFh
7.36
Reserved
Enter Secured OTP (B1h)
The Enter Secured OTP instruction is for entering the additional 4K-bit secured OTP mode. The additional 4K-bit
secured OTP is independent from main array, which may be used to store unique serial number for system identifier.
After entering the Secured OTP mode, and then follow standard read or program, procedure to read out the data or
update data. The Secured OTP data cannot be updated again once it is lock-down
Please note that Write Status Register-1, Write Status Register-2 and Write Security Register instructions are not
acceptable during the access of secure OTP region. Once security OTP is lock down, only commands related with read
are valid. The Enter Secured OTP instruction sequence is shown in Figure 7-59.
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Figure 7-59. Enter Secured OTP instruction for SPI Mode (left) and QPI Mode (right)
7.37
Exit Secured OTP (C1h)
The Exit Secured OTP instruction is for exiting the additional 4K-bit secured OTP mode. (Please refer to Figure 7-60).
Figure 7-60. Exit Secured OTP instruction for SPI Mode (left) and QPI Mode (right)
7.38
Read Security Register (2Bh)
The Read Security Register can be read the value of Security Register bits at any time (even in program/erase/write
status register-1 and write status register-2 condition) and continuously.
Secured OTP Indicator bit. The Secured OTP indicator bit shows the chip is locked by factory before ex-factory or not.
When it is “0”, it indicates non-factory lock, “1” indicates factory-lock.
Lock-down Secured OTP (LDSO) bit. By writing Write Security Register instruction, the LDSO bit may be set to “1” for
customer lock-down purpose. However, once the bit it set to “1” (Lock-down), the LDSO bit and the 4K-bit Secured OTP
area cannot be updated any more. While it is in 4K-bit Secured OTP mode, array access is not allowed to write.
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Table 7-12. Security Register Bit Assignments
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
x
x
x
x
x
x
LDSO
(indicate if lock- down)
Secured OTP
indicator bit
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
0: no lock down
0: non factory lock
1: factory lock
1: lock- down
(cannot program/
erase OTP)
Volatile bit
Volatile bit
Volatile bit
Volatile bit
Volatile bit
Volatile bit
Non Volatile bit
Non-Volatile bit
Figure 7-61. Read Security Register instruction (SPI Mode)
Figure 7-62. Read Security Register instruction (QPI Mode)
7.39
Write Security Register (2Fh)
The Write Security Register instruction is for changing the values of Security Register bits. Unlike Write Status Register,
the Write Enable instruction is not required before writing Write Security Register instruction. The Write Security
Register instruction may change the value of bit1 (LDSO bit) for customer to lock-down the 4K-bit Secured OTP area.
Once the LDSO bit is set to “1”, the Secured OTP area cannot be updated any more.
The CS must go high exactly at the boundary; otherwise, the instruction will be rejected and not executed.
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Figure 7-63. Write Security Register instruction for SPI Mode (left) and QPI Mode (right)
7.40
4K-bit Secured OTP
It’s for unique identifier to provide 4K-bit one-time-program area for setting device unique serial number which may
be set by factory or system customer. Please refer to table of “4K-bit secured OTP definition”.
- Security register bit 0 indicates whether the chip is locked by factory or not.
- To program the 4K-bit secured OTP by entering 4K-bit secured OTP mode (with ENSO command) and going through
normal program procedure, and then exiting 4K-bit secured OTP mode by writing EXSO command
- Customer may lock-down bit1 as “1”. Please refer to “table of security register definition” for security register bit
definition and table of “4K-bit secured OTP definition” for address range definition.
Note. Once lock-down whatever by factory or customer, it cannot be changed any more. While in 4K-bit secured OTP
mode, array access is not allowed to write.
Table 7-13. Addressing of Secured OTP Area
Address Range
Size
Standard
Customer Lock
000000 ~ 00000F
128 bits
ESN (Electrical Serial Number)
Determined by customer
000010 ~ 0001FF
3,968 bits
N/A
AT25SL128A
DS-AT25SL128A–109K–02/2019
63
8.
Electrical Characteristics
Table 8-1.
Electrical Characteristics
Parameter
Symbol
Supply Voltage
VCC
Voltage Applied to Any Pin
VIO
Transient Voltage on any Pin
VIOT
Storage Temperature
TSTG
Lead Temperature
TLEAD
Electrostatic Discharge Voltage
VESD
Conditions
Range
Unit
-0.6 to VCC+0.4
V
Relative to Ground
-0.6 to VCC +0.4
V