EN25LF20
EN25LF20
2 Megabit Serial Flash Memory with 4Kbytes Uniform Sector
FEATURES
• Software and Hardware Write Protection:
- Write Protect all or portion of memory via
software
- Enable/Disable protection with WP# pin
• Single power supply operation
- Full voltage range: 2.35-3.6 volt
• 2 Mbit Serial Flash
- 2 M-bit/256 K-byte/1024 pages
- 256 bytes per programmable page
•
-
• High performance
- 75MHz clock rate
• Low power consumption
- 5 mA typical active current
- 1 μA typical power down current
•
-
High performance program/erase speed
Page program time: 1.5ms typical
Sector erase time: 150ms typical
Block erase time 800ms typical
Chip erase time: 3 Seconds typical
• Lockable 256 byte OTP security sector
• Minimum 100K endurance cycle
Uniform Sector Architecture:
64 sectors of 4-Kbyte
4 blocks of 64-Kbyte
Any sector or block can be
erased individually
•
-
Package Options
8 pins SOP 150mil body width
8 contact VDFN
All Pb-free packages are RoHS compliant
• Industrial temperature Range
GENERAL DESCRIPTION
The EN25LF20 is a 2M-bit (256K-byte) Serial Flash memory, with advanced write protection
mechanisms, accessed by a high speed SPI-compatible bus. The memory can be programmed 1 to
256 bytes at a time, using the Page Program instruction.
The EN25LF20 is designed to allow either single Sector at a time or full chip erase operation. The
EN25LF20 can be configured to protect part of the memory as the software protected mode. The
device can sustain a minimum of 100K program/erase cycles on each sector.
This Data Sheet may be revised by subsequent versions
1
or modifications due to changes in technical specifications.
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Figure.1 CONNECTION DIAGRAMS
8 - LEAD SOP
8 - CONTACT VDFN
Figure 2. BLOCK DIAGRAM
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
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©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
SIGNAL DESCRIPTION
Serial Data Input (DI)
The SPI Serial Data Input (DI) pin provides a means for instructions, addresses and data to be
serially written to (shifted into) the device. Data is latched on the rising edge of the Serial Clock (CLK)
input pin.
Serial Data Output (DO)
The SPI Serial Data Output (DO) pin provides a means for data and status to be serially read from
(shifted out of) the device. Data is shifted out on the falling edge of the Serial Clock (CLK) input pin.
Serial Clock (CLK)
The SPI Serial Clock Input (CLK) pin provides the timing for serial input and output operations. ("See
SPI Mode")
Chip Select (CS#)
The SPI Chip Select (CS#) pin enables and disables device operation. When CS# is high the device
is deselected and the Serial Data Output (DO) pin is at high impedance. When deselected, the
devices power consumption will be at standby levels unless an internal erase, program or status
register cycle is in progress. When CS# is brought low the device will be selected, power
consumption will increase to active levels and instructions can be written to and data read from the
device. After power-up, CS# must transition from high to low before a new instruction will be
accepted.
Hold (HOLD#)
The HOLD# pin allows the device to be paused while it is actively selected. When HOLD# is brought
low, while CS# is low, the DO pin will be at high impedance and signals on the DI and CLK pins will
be ignored (don’t care). The hold function can be useful when multiple devices are sharing the same
SPI signals.
Write Protect (WP#)
The Write Protect (WP#) pin can be used to prevent the Status Register from being written. Used in
conjunction with the Status Register’s Block Protect (BP0, BP1 and BP2) bits and Status Register
Protect (SRP) bits, a portion or the entire memory array can be hardware protected.
Table 1. PIN Names
Symbol
Pin Name
CLK
Serial Clock Input
DI
Serial Data Input
DO
Serial Data Output
CS#
Chip Enable
WP#
Write Protect
HOLD#
Hold Input
Vcc
Supply Voltage (2.35-3.6V)
Vss
Ground
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
3
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
MEMORY ORGANIZATION
The memory is organized as:
z
262,144 bytes
z
Uniform Sector Architecture
4 blocks of 64-Kbyte
64 sectors of 4-Kbyte
z
1024 pages (256 bytes each)
Each page can be individually programmed (bits are programmed from 1 to 0). The device is Sector,
Block or Chip Erasable but not Page Erasable.
Table 2. Uniform Block Sector Architecture
….
020000h
01F000h
020FFFh
01FFFFh
….
32
31
….
….
….
030FFFh
02FFFFh
….
….
030000h
02F000h
16
15
010000h
00F000h
010FFFh
00FFFFh
….
0
48
47
….
1
03FFFFh
03EFFFh
03DFFFh
03CFFFh
03BFFFh
….
2
Address range
03F000h
03E000h
03D000h
03C000h
03B000h
….
3
Sector
63
62
61
60
59
….
Block
4
3
2
1
0
004000h
003000h
002000h
001000h
000000h
004FFFh
003FFFh
002FFFh
001FFFh
000FFFh
OPERATING FEATURES
SPI Modes
The EN25LF20 is accessed through an SPI compatible bus consisting of four signals: Serial Clock
(CLK), Chip Select (CS#), Serial Data Input (DI) and Serial Data Output (DO). Both SPI bus
operation Modes 0 (0,0) and 3 (1,1) are supported. The primary difference between Mode 0 and
Mode 3, as shown in Figure 3, concerns the normal state of the CLK signal when the SPI bus
master is in standby and data is not being transferred to the Serial Flash. For Mode 0 the CLK signal
is normally low. For Mode 3 the CLK signal is normally high. In either case data input on the DI pin is
sampled on the rising edge of the CLK. Data output on the DO pin is clocked out on the falling edge
of CLK.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
4
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Figure 3. SPI Modes
Page Programming
To program one data byte, two instructions are required: Write Enable (WREN), which is one byte,
and a Page Program (PP) sequence, which consists of four bytes plus data. This is followed by the
internal Program cycle (of duration tPP).
To spread this overhead, the Page Program (PP) instruction allows up to 256 bytes to be programmed at a time (changing bits from 1 to 0), provided that they lie in consecutive addresses on
the same page of memory.
Sector Erase, Block Erase and Chip Erase
The Page Program (PP) instruction allows bits to be reset from 1 to 0. Before this can be applied,
the bytes of memory need to have been erased to all 1s (FFh). This can be achieved a sector at a
time, using the Sector Erase (SE) instruction, a block at a time using the Block Erase (BE)
instruction or throughout the entire memory, using the Chip Erase (CE) instruction. This starts an
internal Erase cycle (of duration tSE tBE or tCE). The Erase instruction must be preceded by a Write
Enable (WREN) instruction.
Polling During a Write, Program or Erase Cycle
A further improvement in the time to Write Status Register (WRSR), Program (PP) or Erase (SE, BE
or CE ) can be achieved by not waiting for the worst case delay (tW, tPP, tSE, tBE or tCE). The
Write In Progress (WIP) bit is provided in the Status Register so that the application program can
monitor its value, polling it to establish when the previous Write cycle, Program cycle or Erase cycle
is complete.
Active Power, Stand-by Power and Deep Power-Down Modes
When Chip Select (CS#) is Low, the device is enabled, and in the Active Power mode. When Chip
Select (CS#) is High, the device is disabled, but could remain in the Active Power mode until all
internal cycles have completed (Program, Erase, Write Status Register). The device then goes into
the Stand-by Power mode. The device consumption drops to ICC1.
The Deep Power-down mode is entered when the specific instruction (the Enter Deep Power-down
Mode (DP) instruction) is executed. The device consumption drops further to ICC2. The device remains in this mode until another specific instruction (the Release from Deep Power-down Mode and
Read Device ID (RDI) instruction) is executed.
All other instructions are ignored while the device is in the Deep Power-down mode. This can be
used as an extra software protection mechanism, when the device is not in active use, to protect the
device from inadvertent Write, Program or Erase instructions.
Status Register. The Status Register contains a number of status and control bits that can be read
or set (as appropriate) by specific instructions.
WIP bit. The Write In Progress (WIP) bit indicates whether the memory is busy with a Write Status
Register, Program or Erase cycle.
WEL bit. The Write Enable Latch (WEL) bit indicates the status of the internal Write Enable Latch.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
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©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
BP2, BP1, BP0 bits. The Block Protect (BP2, BP1, BP0) bits are non-volatile. They define the size
of the area to be software protected against Program and Erase instructions.
SRP bit / OTP_LOCK bit The Status Register Protect (SRP) bit is operated in conjunction with the
Write Protect (WP#) signal. The Status Register Protect (SRP) bit and Write Protect (WP#) signal
allow the device to be put in the Hardware Protected mode. In this mode, the non-volatile bits of the
Status Register (SRP, BP2, BP1, BP0) become read-only bits.
In OTP mode, this bit is served as OTP_LOCK bit, user can read/program/erase OTP sector as
normal sector while OTP_LOCK value is equal 0, after OTP_LOCK is programmed with 1 by WRSR
command, the OTP sector is protected from program and erase operation. The OTP_LOCK bit can
only be programmed once.
Note : In OTP mode, the WRSR command will ignore any input data and program OTP_LOCK bit to
1, user must clear the protect bits before enter OTP mode and program the OTP code, then execute
WRSR command to lock the OTP sector before leaving OTP mode.
Write Protection
Applications that use non-volatile memory must take into consideration the possibility of noise and
other adverse system conditions that may compromise data integrity. To address this concern the
EN25LF20 provides the following data protection mechanisms:
z
Power-On Reset and an internal timer (tPUW) can provide protection against inadvertent
changes while the power supply is outside the operating specification.
z
Program, Erase and Write Status Register instructions are checked that they consist of a
number of clock pulses that is a multiple of eight, before they are accepted for execution.
z
All instructions that modify data must be preceded by a Write Enable (WREN) instruction to set
the Write Enable Latch (WEL) bit . This bit is returned to its reset state by the following events:
– Power-up
– Write Disable (WRDI) instruction completion or Write Status Register (WRSR) instruction
completion or Page Program (PP) instruction completion or Sector Erase (SE) instruction
completion or Block Erase (BE) instruction completion or Chip Erase (CE) instruction
completion
z
The Block Protect (BP2, BP1, BP0) bits allow part of the memory to be configured as read-only.
This is the Software Protected Mode (SPM).
z
The Write Protect (WP#) signal allows the Block Protect (BP2, BP1, BP0) bits and Status
Register Protect (SRP) bit to be protected. This is the Hardware Protected Mode (HPM).
z
In addition to the low power consumption feature, the Deep Power-down mode offers extra
software protection from inadvertent Write, Program and Erase instructions, as all instructions
are ignored except one particular instruction (the Release from Deep Power-down instruction).
TABLE 3. Protected Area Sizes Sector Organization
Status Register
Content
BP2
BP1
BP0
Bit
Bit
Bit
1
1
1
1
1
0
1
0
1
1
0
0
0
1
1
0
1
0
0
0
1
0
0
0
Memory Content
Protect
Addresses
000000h-03FFFFh
000000h-03DFFFh
000000h-03BFFFh
Protect
Density(KB)
256KB
248KB
240KB
All
Lower 31/32
Lower 30/32
None
None
None
None
All
Block 2 to 3
Block 3
None
000000h-03FFFFh
020000h-03FFFFh
030000h-03FFFFh
None
256KB
128KB
64KB
None
All
Upper 1/2
Upper 1/4
None
Protect Blocks
All
sector 0 to sector 61
sector 0 to sector 59
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
6
Protect
Portion
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Hold Function
The Hold (HOLD#) signal is used to pause any serial communications with the device without resetting
the clocking sequence. However, taking this signal Low does not terminate any Write Status Register,
Program or Erase cycle that is currently in progress.
To enter the Hold condition, the device must be selected, with Chip Select (CS#) Low. The Hold condition
starts on the falling edge of the Hold (HOLD#) signal, provided that this coincides with Serial Clock (CLK)
being Low (as shown in Figure 4.).
The Hold condition ends on the rising edge of the Hold (HOLD#) signal, provided that this coincides with
Serial Clock (CLK) being Low.
If the falling edge does not coincide with Serial Clock (CLK) being Low, the Hold condition starts after
Serial Clock (CLK) next goes Low. Similarly, if the rising edge does not coincide with Serial Clock (CLK)
being Low, the Hold condition ends after Serial Clock (CLK) next goes Low. (This is shown in Figure 4.).
During the Hold condition, the Serial Data Output (DO) is high impedance, and Serial Data Input (DI) and
Serial Clock (CLK) are Don’t Care.
Normally, the device is kept selected, with Chip Select (CS#) driven Low, for the whole duration of the
Hold condition. This is to ensure that the state of the internal logic remains unchanged from the moment
of entering the Hold condition.
If Chip Select (CS#) goes High while the device is in the Hold condition, this has the effect of resetting the
internal logic of the device. To restart communication with the device, it is necessary to drive Hold
(HOLD#) High, and then to drive Chip Select (CS#) Low. This prevents the device from going back to the
Hold condition.
Figure 4. Hold Condition Waveform
INSTRUCTIONS
All instructions, addresses and data are shifted in and out of the device, most significant bit first.
Serial Data Input (DI) is sampled on the first rising edge of Serial Clock (CLK) after Chip Select (CS#)
is driven Low. Then, the one-byte instruction code must be shifted in to the device, most significant
bit first, on Serial Data Input (DI), each bit being latched on the rising edges of Serial Clock (CLK).
The instruction set is listed in Table 4. Every instruction sequence starts with a one-byte instruction
code. Depending on the instruction, this might be followed by address bytes, or by data bytes, or by
both or none. Chip Select (CS#) must be driven High after the last bit of the instruction sequence
has been shifted in. In the case of a Read Data Bytes (READ), Read Data Bytes at Higher Speed
(Fast_Read), Read Status Register (RDSR) or Release from Deep Power-down, and Read Device
ID (RDI) instruction, the shifted-in instruction sequence is followed by a data-out sequence. Chip
Select (CS#) can be driven High after any bit of the data-out sequence is being shifted out.
In the case of a Page Program (PP), Sector Erase (SE), Block Erase (BE), Chip Erase (CE), Write
Status Register (WRSR), Write Enable (WREN), Write Disable (WRDI) or Deep Power-down (DP)
instruction, Chip Select (CS#) must be driven High exactly at a byte boundary, otherwise the
instruction is rejected, and is not executed. That is, Chip Select (CS#) must driven High when the
number of clock pulses after Chip Select (CS#) being driven Low is an exact multiple of eight. For
Page Program, if at any time the input byte is not a full byte, nothing will happen and WEL will not be
reset.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
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©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
In the case of multi-byte commands of Page Program (PP), and Release from Deep Power
Down (RES ) minimum number of bytes specified has to be given, without which, the
command will be ignored.
In the case of Page Program, if the number of byte after the command is less than 4 (at least
1 data byte), it will be ignored too. In the case of SE and BE, exact 24-bit address is a must,
any less or more will cause the command to be ignored.
All attempts to access the memory array during a Write Status Register cycle, Program cycle or
Erase cycle are ignored, and the internal Write Status Register cycle, Program cycle or Erase cycle
continues unaffected.
Table 4. Instruction Set
Instruction Name
Byte 1
Code
Write Enable
Write Disable / Exit
OTP mode
Read Status
Register
Write Status
Register
Read Data
06h
Byte 2
Byte 3
Byte 4
Byte 5
Byte 6
n-Bytes
04h
continuous
(2)
05h
(S7-S0)(1)
01h
S7-S0
03h
A23-A16
A15-A8
A7-A0
(D7-D0)
(Next byte)
Fast Read
0Bh
A23-A16
A15-A8
A7-A0
dummy
(D7-D0)
Page Program
02h
A23-A16
A15-A8
A7-A0
D7-D0
Next byte
Sector Erase
20h
A23-A16
A15-A8
A7-A0
Block Erase
D8h/ 52h
A23-A16
A15-A8
A7-A0
Chip Erase
C7h/ 60h
Deep Power-down
Release from Deep
Power-down, and
read Device ID
Release from Deep
Power-down
Manufacturer/
Device ID
Read Identification
Enter OTP mode
B9h
continuous
(Next Byte)
continuous
continuous
(4)
dummy
dummy
dummy
dummy
dummy
00h(5)
(M7-M0)
(ID15-ID8)
(ID7-ID0)
(ID7-ID0)
ABh
90h
9Fh
3Ah
(M7-M0)
(ID7-ID0)
Notes:
1. Data bytes are shifted with Most Significant Bit first. Byte fields with data in parenthesis “( )” indicate data being read from
the device on the DO pin.
2. The Status Register contents will repeat continuously until CS# terminate the instruction.
3. All sectors may use any address within the sector.
4. The Device ID will repeat continuously until CS# terminate the instruction.
5. The Manufacturer ID and Device ID bytes will repeat continuously until CS# terminate the instruction.
00h on Byte 4 starts with MID and alternate with DID, 01h on Byte 4 starts with DID and alternate with MID.
Table 5. Manufacturer and Device Identification
OP Code
(M7-M0)
(ID15-ID0)
ABh
(ID7-ID0)
11h
90h
1Ch
9Fh
1Ch
11h
3112h
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
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©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Write Enable (WREN) (06h)
The Write Enable (WREN) instruction (Figure 5) sets the Write Enable Latch (WEL) bit. The Write
Enable Latch (WEL) bit must be set prior to every Page Program (PP), Sector Erase (SE), Block
Erase (BE), Chip Erase (CE) and Write Status Register (WRSR) instruction.
The Write Enable (WREN) instruction is entered by driving Chip Select (CS#) Low, sending the
instruction code, and then driving Chip Select (CS#) High.
Figure 5. Write Enable Instruction Sequence Diagram
Write Disable (WRDI) (04h)
The Write Disable instruction (Figure 6) resets the Write Enable Latch (WEL) bit in the Status
Register to a 0 or exit from OTP mode to normal mode. The Write Disable instruction is entered by
driving Chip Select (CS#) low, shifting the instruction code “04h” into the DI pin and then driving Chip
Select (CS#) high. Note that the WEL bit is automatically reset after Power-up and upon completion
of the Write Status Register, Page Program, Sector Erase, Block Erase (BE) and Chip Erase
instructions.
Figure 6. Write Disable Instruction Sequence Diagram
Read Status Register (RDSR) (05h)
The Read Status Register (RDSR) instruction allows the Status Register to be read. The Status
Register may be read at any time, even while a Program, Erase or Write Status Register cycle is in
progress. When one of these cycles is in progress, it is recommended to check the Write In
Progress (WIP) bit before sending a new instruction to the device. It is also possible to read the
Status Register continuously, as shown in Figure 7.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
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©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Figure 7. Read Status Register Instruction Sequence Diagram
Table 6. Status Register Bit Locations
S7
S6
S5
S4
S3
S2
S1
S0
SRP
0
0
BP2
BP1
BP0
WEL
WIP
Status Register Protect
Reserved Bits
Block Protect Bits
Write Enable Latch
Write In Progress
Note : In OTP mode, SRP bit is served as OTP_LOCK bit.
The status and control bits of the Status Register are as follows:
WIP bit. The Write In Progress (WIP) bit indicates whether the memory is busy with a Write Status
Register, Program or Erase cycle. When set to 1, such a cycle is in progress, when reset to 0 no
such cycle is in progress.
WEL bit. The Write Enable Latch (WEL) bit indicates the status of the internal Write Enable Latch.
When set to 1 the internal Write Enable Latch is set, when set to 0 the internal Write Enable Latch is
reset and no Write Status Register, Program or Erase instruction is accepted.
BP2, BP1, BP0 bits. The Block Protect (BP2, BP1, BP0) bits are non-volatile. They define the size
of the area to be software protected against Program and Erase instructions. These bits are written
with the Write Status Register (WRSR) instruction. When one or both of the Block Protect (BP2, BP1,
BP0) bits is set to 1, the relevant memory area (as defined in Table 3.) becomes protected against
Page Program (PP) Sector Erase (SE) and , Block Erase (BE), instructions. The Block Protect (BP2,
BP1, BP0) bits can be written provided that the Hardware Protected mode has not been set. The
Chip Erase (CE) instruction is executed if, and only if, both Block Protect (BP2, BP1, BP0) bits are 0.
Reserved bit. Status register bit locations 5 and 6 are reserved for future use. Current devices will
read 0 for these bit locations. It is recommended to mask out the reserved bit when testing the
Status Register. Doing this will ensure compatibility with future devices.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
10
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
SRP bit / OTP_LOCK bit. The Status Register Protect (SRP) bit is operated in conjunction with the
Write Protect (WP#) signal. The Status Register Write Protect (SRP) bit and Write Protect (WP#)
signal allow the device to be put in the Hardware Protected mode (when the Status Register Protect
(SRP) bit is set to 1, and Write Protect (WP#) is driven Low). In this mode, the non-volatile bits of the
Status Register (SRP, BP2, BP1, BP0) become read-only bits and the Write Status Register (WRSR)
instruction is no longer accepted for execution.
In OTP mode, this bit is served as OTP_LOCK bit, user can read/program/erase OTP sector as
normal sector while OTP_LOCK value is equal 0, after OTP_LOCK is programmed with 1 by WRSR
command, the OTP sector is protected from program and erase operation. The OTP_LOCK bit can
only be programmed once.
Note : In OTP mode, the WRSR command will ignore any input data and program OTP_LOCK bit to
1, user must clear the protect bits before enter OTP mode and program the OTP code, then execute
WRSR command to lock the OTP sector before leaving OTP mode.
Write Status Register (WRSR) (01h)
The Write Status Register (WRSR) instruction allows new values to be written to the Status Register.
Before it can be accepted, a Write Enable (WREN) instruction must previously have been executed.
After the Write Enable (WREN) instruction has been decoded and executed, the device sets the
Write Enable Latch (WEL).
The Write Status Register (WRSR) instruction is entered by driving Chip Select (CS#) Low, followed
by the instruction code and the data byte on Serial Data Input (DI).
The instruction sequence is shown in Figure 8. The Write Status Register (WRSR) instruction has
no effect on S6, S5, S1 and S0 of the Status Register. S6 and S5 are always read as 0. Chip Select
(CS#) must be driven High after the eighth bit of the data byte has been latched in. If not, the Write
Status Register (WRSR) instruction is not executed. As soon as Chip Select (CS#) is driven High,
the self-timed Write Status Register cycle (whose duration is tW) is initiated. While the Write Status
Register cycle is in progress, the Status Register may still be read to check the value of the Write In
Progress (WIP) bit. The Write In Progress (WIP) bit is 1 during the self-timed Write Status Register
cycle, and is 0 when it is completed. When the cycle is completed, the Write Enable Latch (WEL) is
reset.
The Write Status Register (WRSR) instruction allows the user to change the values of the Block
Protect (BP2, BP1, BP0) bits, to define the size of the area that is to be treated as read-only, as defined in Table 3.. The Write Status Register (WRSR) instruction also allows the user to set or reset
the Status Register Protect (SRP) bit in accordance with the Write Protect (WP#) signal. The Status
Register Protect (SRP) bit and Write Protect (WP#) signal allow the device to be put in the Hardware
Protected Mode (HPM). The Write Status Register (WRSR) instruction is not executed once the
Hardware Protected Mode (HPM) is entered.
NOTE : In the OTP mode, WRSR command will ignore input data and program OTP_LOCK bit to 1.
Figure 8. Write Status Register Instruction Sequence Diagram
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
11
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Read Data Bytes (READ) (03h)
The device is first selected by driving Chip Select (CS#) Low. The instruction code for the Read Data
Bytes (READ) instruction is followed by a 3-byte address (A23-A0), each bit being latched-in during
the rising edge of Serial Clock (CLK). Then the memory contents, at that address, is shifted out on
Serial Data Output (DO), each bit being shifted out, at a maximum frequency fR, during the falling
edge of Serial Clock (CLK).
The instruction sequence is shown in Figure 9. The first byte addressed can be at any location. The
address is automatically incremented to the next higher address after each byte of data is shifted out.
The whole memory can, therefore, be read with a single Read Data Bytes (READ) instruction. When
the highest address is reached, the address counter rolls over to 000000h, allowing the read
sequence to be continued indefinitely.
The Read Data Bytes (READ) instruction is terminated by driving Chip Select (CS#) High. Chip
Select (CS#) can be driven High at any time during data output. Any Read Data Bytes (READ)
instruction, while an Erase, Program or Write cycle is in progress, is rejected without having any
effects on the cycle that is in progress.
Figure 9. Read Data Instruction Sequence Diagram
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
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©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Read Data Bytes at Higher Speed (FAST_READ) (0Bh)
The device is first selected by driving Chip Select (CS#) Low. The instruction code for the Read Data
Bytes at Higher Speed (FAST_READ) instruction is followed by a 3-byte address (A23-A0) and a
dummy byte, each bit being latched-in during the rising edge of Serial Clock (CLK). Then the
memory contents, at that address, is shifted out on Serial Data Output (DO), each bit being shifted
out, at a maximum frequency FR, during the falling edge of Serial Clock (CLK).
The instruction sequence is shown in Figure 10. The first byte addressed can be at any location.
The address is automatically incremented to the next higher address after each byte of data is shifted out. The whole memory can, therefore, be read with a single Read Data Bytes at Higher Speed
(FAST_READ) instruction. When the highest address is reached, the address counter rolls over to
000000h, allowing the read sequence to be continued indefinitely.
The Read Data Bytes at Higher Speed (FAST_READ) instruction is terminated by driving Chip
Select (CS#) High. Chip Select (CS#) can be driven High at any time during data output. Any Read
Data Bytes at Higher Speed (FAST_READ) instruction, while an Erase, Program or Write cycle is in
progress, is rejected without having any effects on the cycle that is in progress.
Figure 10. Fast Read Instruction Sequence Diagram
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
13
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Page Program (PP) (02h)
The Page Program (PP) instruction allows bytes to be programmed in the memory. Before it can be
accepted, a Write Enable (WREN) instruction must previously have been executed. After the Write
Enable (WREN) instruction has been decoded, the device sets the Write Enable Latch (WEL).
The Page Program (PP) instruction is entered by driving Chip Select (CS#) Low, followed by the instruction code, three address bytes and at least one data byte on Serial Data Input (DI). If the 8 least
significant address bits (A7-A0) are not all zero, all transmitted data that goes beyond the end of the
current page are programmed from the start address of the same page (from the address whose 8
least significant bits (A7-A0) are all zero). Chip Select (CS#) must be driven Low for the entire
duration of the sequence.
The instruction sequence is shown in Figure 11. If more than 256 bytes are sent to the device, previously latched data are discarded and the last 256 data bytes are guaranteed to be programmed
correctly within the same page. If less than 256 Data bytes are sent to device, they are correctly programmed at the requested addresses without having any effects on the other bytes of the same
page.
Chip Select (CS#) must be driven High after the eighth bit of the last data byte has been latched in,
otherwise the Page Program (PP) instruction is not executed.
As soon as Chip Select (CS#) is driven High, the self-timed Page Program cycle (whose duration is
tPP) is initiated. While the Page Program cycle is in progress, the Status Register may be read to
check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is 1 during the
self-timed Page Program cycle, and is 0 when it is completed. At some unspecified time before the
cycle is completed, the Write Enable Latch (WEL) bit is reset.
A Page Program (PP) instruction applied to a page which is protected by the Block Protect (BP2,
BP1, BP0) bits (see Table 3) is not executed.
Figure 11. Page Program Instruction Sequence Diagram
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
14
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Sector Erase (SE) (20h)
The Sector Erase (SE) instruction sets to 1 (FFh) all bits inside the chosen sector. Before it can be
accepted, a Write Enable (WREN) instruction must previously have been executed. After the Write
Enable (WREN) instruction has been decoded, the device sets the Write Enable Latch (WEL).
The Sector Erase (SE) instruction is entered by driving Chip Select (CS#) Low, followed by the instruction code, and three address bytes on Serial Data Input (DI). Any address inside the Sector
(see Table 2) is a valid address for the Sector Erase (SE) instruction. Chip Select (CS#) must be
driven Low for the entire duration of the sequence.
The instruction sequence is shown in Figure 12. Chip Select (CS#) must be driven High after the
eighth bit of the last address byte has been latched in, otherwise the Sector Erase (SE) instruction is
not executed. As soon as Chip Select (CS#) is driven High, the self-timed Sector Erase cycle
(whose duration is tSE) is initiated. While the Sector Erase cycle is in progress, the Status Register
may be read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is
1 during the self-timed Sector Erase cycle, and is 0 when it is completed. At some unspecified time
before the cycle is completed, the Write Enable Latch (WEL) bit is reset.
A Sector Erase (SE) instruction applied to a sector which is protected by the Block Protect (BP2,
BP1, BP0) bits (see Table 3) is not executed.
Figure 12. Sector Erase Instruction Sequence Diagram
Block Erase (BE) (D8h/52h)
The Block Erase (BE) instruction sets to 1 (FFh) all bits inside the chosen block. Before it can be
accepted, a Write Enable (WREN) instruction must previously have been executed. After the Write
Enable (WREN) instruction has been decoded, the device sets the Write Enable Latch (WEL).
The Block Erase (BE) instruction is entered by driving Chip Select (CS#) Low, followed by the instruction code, and three address bytes on Serial Data Input (DI). Any address inside the Block (see
Table 2) is a valid address for the Block Erase (BE) instruction. Chip Select (CS#) must be driven
Low for the entire duration of the sequence.
The instruction sequence is shown in Figure 13. Chip Select (CS#) must be driven High after the
eighth bit of the last address byte has been latched in, otherwise the Block Erase (BE) instruction is
not executed. As soon as Chip Select (CS#) is driven High, the self-timed Block Erase cycle (whose
duration is tSE) is initiated. While the Block Erase cycle is in progress, the Status Register may be
read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is 1
during the self-timed Block Erase cycle, and is 0 when it is completed. At some unspecified time
before the cycle is completed, the Write Enable Latch (WEL) bit is reset.
A Block Erase (BE) instruction applied to a block which is protected by the Block Protect (BP2, BP1,
BP0) bits (see Table 3) is not executed.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
15
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Figure 13 Block Erase Instruction Sequence Diagram
Chip Erase (CE) (C7h/60h)
The Chip Erase (CE) instruction sets all bits to 1 (FFh). Before it can be accepted, a Write Enable
(WREN) instruction must previously have been executed. After the Write Enable (WREN) instruction
has been decoded, the device sets the Write Enable Latch (WEL).
The Chip Erase (CE) instruction is entered by driving Chip Select (CS#) Low, followed by the
instruction code on Serial Data Input (DI). Chip Select (CS#) must be driven Low for the entire
duration of the sequence.
The instruction sequence is shown in Figure 14. Chip Select (CS#) must be driven High after the
eighth bit of the instruction code has been latched in, otherwise the Chip Erase instruction is not
executed. As soon as Chip Select (CS#) is driven High, the self-timed Chip Erase cycle (whose
duration is tCE) is initiated. While the Chip Erase cycle is in progress, the Status Register may be
read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is 1
during the self-timed Chip Erase cycle, and is 0 when it is completed. At some unspecified time
before the cycle is completed, the Write Enable Latch (WEL) bit is reset.
The Chip Erase (CE) instruction is executed only if all Block Protect (BP2, BP1, BP0) bits are 0. The
Chip Erase (CE) instruction is ignored if one, or more, sectors are protected.
Figure 14. Chip Erase Instruction Sequence Diagram
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
16
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Deep Power-down (DP) (B9h)
Executing the Deep Power-down (DP) instruction is the only way to put the device in the lowest consumption mode (the Deep Power-down mode). It can also be used as an extra software protection
mechanism, while the device is not in active use, since in this mode, the device ignores all Write,
Program and Erase instructions.
Driving Chip Select (CS#) High deselects the device, and puts the device in the Standby mode (if
there is no internal cycle currently in progress). But this mode is not the Deep Power-down mode.
The Deep Power-down mode can only be entered by executing the Deep Power-down (DP)
instruction, to reduce the standby current (from ICC1 to ICC2, as specified in Table 8.).
Once the device has entered the Deep Power-down mode, all instructions are ignored except the
Release from Deep Power-down and Read Device ID (RDI) instruction. This releases the device
from this mode. The Release from Deep Power-down and Read Device ID (RDI) instruction also
allows the Device ID of the device to be output on Serial Data Output (DO).
The Deep Power-down mode automatically stops at Power-down, and the device always Powers-up
in the Standby mode. The Deep Power-down (DP) instruction is entered by driving Chip Select (CS#)
Low, followed by the instruction code on Serial Data Input (DI). Chip Select (CS#) must be driven
Low for the entire duration of the sequence.
The instruction sequence is shown in Figure 15..Chip Select (CS#) must be driven High after the
eighth bit of the instruction code has been latched in, otherwise the Deep Power-down (DP)
instruction is not executed. As soon as Chip Select (CS#) is driven High, it requires a delay of tDP
before the supply current is reduced to ICC2 and the Deep Power-down mode is entered.
Any Deep Power-down (DP) instruction, while an Erase, Program or Write cycle is in progress, is
rejected without having any effects on the cycle that is in progress.
Figure 15. Deep Power-down Instruction Sequence Diagram
Release from Deep Power-down and Read Device ID (RDI)
Once the device has entered the Deep Power-down mode, all instructions are ignored except the
Release from Deep Power-down and Read Device ID (RDI) instruction. Executing this instruction
takes the device out of the Deep Power-down mode.
Please note that this is not the same as, or even a subset of, the JEDEC 16-bit Electronic Signature
that is read by the Read Identifier (RDID) instruction. The old-style Electronic Signature is supported
for reasons of backward compatibility, only, and should not be used for new designs. New designs
should, instead, make use of the JEDEC 16-bit Electronic Signature, and the Read Identifier (RDID)
instruction.
When used only to release the device from the power-down state, the instruction is issued by driving
the CS# pin low, shifting the instruction code “ABh” and driving CS# high as shown in Figure 16.
After the time duration of tRES1 (See AC Characteristics) the device will resume normal operation
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
17
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
and other instructions will be accepted. The CS# pin must remain high during the tRES1 time
duration.
When used only to obtain the Device ID while not in the power-down state, the instruction is initiated
by driving the CS# pin low and shifting the instruction code “ABh” followed by 3-dummy bytes. The
Device ID bits are then shifted out on the falling edge of CLK with most significant bit (MSB) first as
shown in Figure 17. The Device ID value for the EN25LF20 is listed in Table 5. The Device ID can
be read continuously. The instruction is completed by driving CS# high.
When Chip Select (CS#) is driven High, the device is put in the Stand-by Power mode. If the device
was not previously in the Deep Power-down mode, the transition to the Stand-by Power mode is
immediate. If the device was previously in the Deep Power-down mode, though, the transition to the
Standby Power mode is delayed by tRES2, and Chip Select (CS#) must remain High for at least
tRES2 (max), as specified in Table 10. Once in the Stand-by Power mode, the device waits to be
selected, so that it can receive, decode and execute instructions.
Except while an Erase, Program or Write Status Register cycle is in progress, the Release from
Deep Power-down and Read Device ID (RDI) instruction always provides access to the 8bit Device
ID of the device, and can be applied even if the Deep Power-down mode has not been entered.
Any Release from Deep Power-down and Read Device ID (RDI) instruction while an Erase, Program
or Write Status Register cycle is in progress, is not decoded, and has no effect on the cycle that is in
progress.
Figure 16. Release Power-down Instruction Sequence Diagram
Figure 17. Release Power-down / Device ID Instruction Sequence Diagram
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
18
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Read Manufacturer / Device ID (90h)
The Read Manufacturer/Device ID instruction is an alternative to the Release from Power-down /
Device ID instruction that provides both the JEDEC assigned manufacturer ID and the specific
device ID.
The Read Manufacturer/Device ID instruction is very similar to the Release from Power-down /
Device ID 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 Eon (1Ch) and the Device ID are shifted out on the falling edge of CLK with most
significant bit (MSB) first as shown in Figure 17. The Device ID values for the EN25LF20 are listed in
Table 5. If the 24-bit address is initially set to 000001h the Device ID will be read first
Figure 18. Read Manufacturer / Device ID Diagram
Read Identification (RDID)(9Fh)
The Read Identification (RDID) instruction allows the 8-bit manufacturer identification to be read,
followed by two bytes of device identification. The device identification indicates the memory type in
the first byte , and the memory capacity of the device in the second byte .
Any Read Identification (RDID) instruction while an Erase or Program cycle is in progress, is not
decoded, and has no effect on the cycle that is in progress. The Read Identification (RDID)
instruction should not be issued while the device is in Deep Power down mode.
The device is first selected by driving Chip Select Low. Then, the 8-bit instruction code for the
instruction is shifted in. This is followed by the 24-bit device identification, stored in the memory,
being shifted out on Serial Data Output each bit being shifted out during the falling edge of Serial
Clock . The instruction sequence is shown in Figure 19. The Read Identification (RDID) instruction is
terminated by driving Chip Select High at any time during data output.
When Chip Select is driven High, the device is put in the Standby Power mode. Once in the Standby
Power mode, the device waits to be selected, so that it can receive, decode and execute instructions.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
19
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Figure 19. Read Identification (RDID)
Enter OTP Mode (3Ah)
This Flash has a extra 256 bytes OTP sector, user must issue ENTER OTP MODE command to
enter OTP mode before reading / programming or erasing OTP sector. After entering OTP mode,
the OTP sector is mapping to sector 63, SRP bit becomes OTP_LOCK bit and can be read with
RDSR command. Program / Erase command will be disabled when OTP_LOCK is ‘1’
WRSR command will ignore the input data and program LOCK_BIT to 1.
User must clear the protect bits before enter OTP mode.
OTP sector can only be program and erase when LOCK_BIT equal ‘0’ and BP [2:0] = ‘000’. In OTP
mode, user can read other sectors, but program/erase other sectors only allowed when OTP_LOCK
equal ‘0’.
User can use WRDI (04H) command to exit OTP mode.
Figure 20. Enter OTP Mode
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
20
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Power-up Timing
Figure 21. Power-up Timing
Table 7. Power-Up Timing and Write Inhibit Threshold
Symbol
Parameter
Min.
Max.
Unit
tVSL(1)
VCC(min) to CS# low
10
tPUW(1)
Time delay to Write instruction
1
10
ms
Write Inhibit Voltage
1
2.2
V
VWI(1)
µs
Note:
1.The parameters are characterized only.
INITIAL DELIVERY STATE
The device is delivered with the memory array erased: all bits are set to 1 (each byte contains FFh). The
Status Register contains 00h (all Status Register bits are 0).
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
21
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Table 8. DC Characteristics
(Ta = - 40°C to 85°C; VCC = 2.35-3.6V)
Symbol
Parameter
Test Conditions
Min.
Max.
Unit
ILI
Input Leakage Current
±2
µA
ILO
Output Leakage Current
±2
µA
ICC1
Standby Current
5
µA
ICC2
Deep Power-down Current
5
µA
ICC3
Operating Current (READ)
ICC4
20
mA
Operating Current (PP)
CS# = VCC, VIN = VSS or VCC
CS# = VCC, VIN = VSS or VCC
CLK = 0.1 VCC / 0.9 VCC at
75MHz, Q = open
CS# = VCC
15
mA
ICC5
Operating Current (WRSR)
CS# = VCC
15
mA
ICC6
Operating Current (SE)
15
mA
ICC7
Operating Current (BE)
CS# = VCC
CS# = VCC
15
mA
VIL
Input Low Voltage
– 0.5
0.2 VCC
V
VIH
Input High Voltage
0.7VCC
VCC+0.4
V
VOL
Output Low Voltage
IOL = 1.6 mA
0.4
V
VOH
Output High Voltage
IOH = –100 µA
VCC-0.2
V
Table 9. AC Measurement Conditions
Symbol
CL
Parameter
Min.
Max.
Load Capacitance
20/30
Input Rise and Fall Times
Unit
pF
5
ns
Input Pulse Voltages
0.2VCC to 0.8VCC
V
Input Timing Reference Voltages
0.3VCC to 0.7VCC
V
VCC / 2
V
Output Timing Reference Voltages
Notes:
1.
CL = 30 pF when CLK=75MHz,
Figure 22. AC Measurement I/O Waveform
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
22
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Table 10. 75MHz AC Characteristics
(Ta = - 40°C to 85°C; VCC = 2.35-3.6V)
Symbol
FR
Alt
fC
fR
tCLH
Parameter
Serial Clock Frequency for:
FAST_READ, PP, SE, BE, DP, RES, WREN,
WRDI, WRSR
Serial Clock Frequency for READ, RDSR, RDID
1
Min
Typ
Max
Unit
D.C.
75
MHz
D.C.
33
MHz
Serial Clock High Time
6
ns
Serial Clock Low Time
6
ns
Serial Clock Rise Time (Slew Rate)
0.1
V / ns
Serial Clock Fall Time (Slew Rate)
0.1
V / ns
CS# Active Setup Time
5
ns
tCHSH
CS# Active Hold Time
5
ns
tSHCH
CS# Not Active Setup Time
5
ns
tCHSL
CS# Not Active Hold Time
5
ns
100
ns
tCLL1
tCLCH
2
tCHCL 2
tSLCH
tCSS
tSHSL
tCSH
CS# High Time
tSHQZ 2
tDIS
Output Disable Time
tCLQX
tHO
Output Hold Time
0
ns
tDVCH
tDSU
Data In Setup Time
2
ns
tCHDX
tDH
Data In Hold Time
5
ns
tHLCH
HOLD# Low Setup Time ( relative to CLK )
5
ns
tHHCH
HOLD# High Setup Time ( relative to CLK )
5
ns
tCHHH
HOLD# Low Hold Time ( relative to CLK )
5
ns
tCHHL
HOLD# High Hold Time ( relative to CLK )
5
ns
6
ns
tHLQZ
2
tHZ
HOLD# Low to High-Z Output
6
ns
tHHQZ
2
tLZ
HOLD# High to Low-Z Output
6
ns
tV
Output Valid from CLK
6
ns
tCLQV
tWHSL3
Write Protect Setup Time before CS# Low
20
ns
tSHWL3
Write Protect Hold Time after CS# High
100
ns
tDP 2
CS# High to Deep Power-down Mode
tRES1 2
tRES2 2
CS# High to Standby Mode without Electronic
Signature read
CS# High to Standby Mode with Electronic
Signature read
tW
Write Status Register Cycle Time
tPP
3
µs
3
µs
1.8
µs
10
15
ms
Page Programming Time
1.5
5
ms
tSE
Sector Erase Time
0.15
0.3
s
tBE
Block Erase Time
0.8
2
s
tCE
Chip Erase Time
3
6
s
Note: 1. TCLKH + TCLKL must be greater than or equal to 1/ FCLK
2. Value guaranteed by characterization, not 100% tested in production.
3. Only applicable as a constraint for a Write status Register instruction when Status Register Protect Bit is set at 1.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
23
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Figure 23. Serial Output Timing
Figure 24. Input Timing
Figure 25. Hold Timing
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
24
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
ABSOLUTE MAXIMUM RATINGS
Stresses above the values so mentioned above may cause permanent damage to the device. These
values are for a stress rating only and do not imply that the device should be operated at conditions
up to or above these values. Exposure of the device to the maximum rating values for extended
periods of time may adversely affect the device reliability.
Parameter
Value
Unit
Storage Temperature
-65 to +125
°C
Plastic Packages
-65 to +125
°C
Output Short Circuit Current1
200
mA
Input and Output Voltage (with respect to
ground) 2
-0.5 to +4.0
V
Vcc
-0.5 to +4.0
V
Notes:
1.
No more than one output shorted at a time. Duration of the short circuit should not be greater than one second.
2.
Minimum DC voltage on input or I/O pins is –0.5 V. During voltage transitions, inputs may undershoot Vss to –1.0V for
periods of up to 50ns and to –2.0 V for periods of up to 20ns. See figure below. Maximum DC voltage on output and I/O
pins is Vcc + 0.5 V. During voltage transitions, outputs may overshoot to Vcc + 1.5 V for periods up to 20ns. See figure
below.
RECOMMENDED OPERATING RANGES 1
Parameter
Value
Ambient Operating Temperature
Industrial Devices
-40 to 85
Operating Supply Voltage
Vcc
Full: 2.35 to 3.6
Unit
°C
V
Notes:
1. Recommended Operating Ranges define those limits between which the functionality of the device is guaranteed.
Vcc
+1.5V
Maximum Negative Overshoot Waveform
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
Maximum Positive Overshoot Waveform
25
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Table 11. DATA RETENTION and ENDURANCE
Parameter Description
Test Conditions
Min
Unit
150°C
10
Years
125°C
20
Years
-40 to 85 °C
100k
cycles
Minimum Pattern Data Retention Time
Erase/Program Endurance
Table 12. LATCH UP CHARACTERISTICS
Parameter Description
Min
Max
Input voltage with respect to Vss on all pins except I/O pins
(including A9, Reset and OE#)
-1.0 V
12.0 V
Input voltage with respect to Vss on all I/O Pins
-1.0 V
Vcc + 1.0 V
Vcc Current
-100 mA
100 mA
Note : These are latch up characteristics and the device should never be put under these conditions. Refer to
Absolute Maximum ratings for the actual operating limits.
Table 13. CAPACITANCE
( VCC = 2.35-3.6V)
Parameter Symbol
Parameter Description
Test Setup
Max
Unit
CIN
Input Capacitance
VIN = 0
Typ
6
pF
COUT
Output Capacitance
VOUT = 0
8
pF
Note : Sampled only, not 100% tested, at TA = 25°C and a frequency of 20MHz.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
26
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
PACKAGE MECHANICAL
b
E
E1
Figure 26. SOP 8 ( 150 mil )
e
Detail A
Detail A
DIMENSION IN MM
NOR
MAX
A
--1.75
A1
--0.25
A2
--1.50
D
--5.00
E
--6.20
E1
--4.00
e
1.27
--b
--0.51
L
--1.27
0
0
θ
--0
8
Note : 1. Coplanarity: 0.1 mm
2. Max. allowable mold flash is 0.15 mm
at the pkg ends, 0.25 mm between leads.
SYMBOL
MIN.
1.35
0.10
--4.80
5.80
3.80
--0.33
0.4
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
27
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Figure 27. VDFN8 ( 5x6mm )
DIMENSION IN MM
MIN.
NOR
A
0.76
0.80
A1
0.00
0.02
A2
--0.20
D
5.90
6.00
E
4.90
5.00
D2
4.18
4.23
E2
3.95
4.00
e
--1.27
b
0.35
0.40
L
0.55
0.60
Note : 1. Coplanarity: 0.1 mm
SYMBOL
MAX
0.84
0.04
--6.10
5.10
4.28
4.05
--0.45
0.65
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
28
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
ORDERING INFORMATION
EN25LF20
-
75
G
I
P
PACKAGING CONTENT
(Blank) = Conventional
P = RoHS compliant
TEMPERATURE RANGE
I = Industrial (-40°C to +85°C)
PACKAGE
G = 8-pin 150mil SOP
V = 8-pin VDFN
SPEED
75 = 75 Mhz
BASE PART NUMBER
EN = Eon Silicon Solution Inc.
25LF = 2.5V Serial 4KByte Uniform-Sector
FLASH
20 = 2 Megabit (256K x 8)
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
29
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EN25LF20
Revisions List
Revision No Description
Date
A
B
2008/05/12
2008/06/23
Initial release
Remove C grade option of temperature range in page 1 and
page 29
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
30
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23