STMicroelectronics M95256-WBN3 256kbit and 128kbit serial spi bus eeprom with high speed clock Datasheet

M95256
M95128
256Kbit and 128Kbit Serial SPI Bus EEPROM
With High Speed Clock
FEATURES SUMMARY
■
■
■
■
■
■
■
■
■
■
■
Compatible with SPI Bus Serial Interface
(Positive Clock SPI Modes)
Single Supply Voltage:
– 4.5 to 5.5V for M95xxx
– 2.5 to 5.5V for M95xxx-W
– 1.8 to 5.5V for M95xxx-R
High Speed
– 10MHz Clock Rate, 5ms Write Time
Status Register
Hardware Protection of the Status Register
BYTE and PAGE WRITE (up to 64 Bytes)
Self-Timed Programming Cycle
Adjustable Size Read-Only EEPROM Area
Enhanced ESD Protection
More than 100000 Erase/Write Cycles
More than 40-Year Data Retention
Figure 1. Packages
8
1
PDIP8 (BN)
0.25 mm frame
8
1
SO8 (MN)
150 mil width
8
1
SO8 (MW)
200 mil width
Table 1. Product List
Reference
Part Number
M95256
M95256
M95256-W
M95256-R
M95128
M95128
TSSOP8 (DW)
169 mil width
M95128-W
M95128-R
October 2004
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M95256, M95128
TABLE OF CONTENTS
FEATURES SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Table 1.
Figure 1.
Figure 2.
Figure 3.
Table 2.
Product List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
DIP, SO and TSSOP Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Signal Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
SIGNAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Serial Data Output (Q) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Serial Data Input (D) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Serial Clock (C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Chip Select (S) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Hold (HOLD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Write Protect (W) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
CONNECTING TO THE SPI BUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Figure 4. Bus Master and Memory Devices on the SPI Bus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
SPI Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 5. SPI Modes Supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
OPERATING FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Power-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Power On Reset: VCC Lock-Out Write Protect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Power-down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Active Power and Standby Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Hold Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 6. Hold Condition Activation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
WIP bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
WEL bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
BP1, BP0 bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
SRWD bit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 3. Status Register Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Data Protection and Protocol Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 4. Write-Protected Block Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
MEMORY ORGANIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 7. Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Table 5. Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Write Enable (WREN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 8. Write Enable (WREN) Sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2/39
M95256, M95128
Write Disable (WRDI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 9. Write Disable (WRDI) Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Read Status Register (RDSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
WIP bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
WEL bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
BP1, BP0 bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
SRWD bit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 10.Read Status Register (RDSR) Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Write Status Register (WRSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Table 6. Protection Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 11.Write Status Register (WRSR) Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Read from Memory Array (READ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 12.Read from Memory Array (READ) Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Write to Memory Array (WRITE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 13.Byte Write (WRITE) Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 14.Page Write (WRITE) Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
POWER-UP AND DELIVERY STATE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Power-up State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Initial Delivery State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
MAXIMUM RATING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Table 7. Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
DC AND AC PARAMETERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Table 8. Operating Conditions (M95xxx) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Table 9. Operating Conditions (M95xxx-W). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Table 10. Operating Conditions (M95xxx-R) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Table 11. AC Measurement Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 15.AC Measurement I/O Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 12. Capacitance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 13. DC Characteristics (M95xxx, Device Grade 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 14. DC Characteristics (M95xxx, Device Grade 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 15. DC Characteristics (M95xxx-W, Device Grade 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 16. DC Characteristics (M95xxx-W, Device Grade 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 17. DC Characteristics (M95xxx-R) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 18. AC Characteristics (M95xxx, Device Grade 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Table 19. AC Characteristics (M95xxx, Device Grade 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 20. AC Characteristics (M95xxx-W, Device Grade 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Table 21. AC Characteristics (M95xxx-W, Device Grade 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table 22. AC Characteristics (M95xxx-R) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Figure 16.Serial Input Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 17.Hold Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 18.Output Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
PACKAGE MECHANICAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3/39
M95256, M95128
Figure 19.PDIP8 – 8 pin Plastic DIP, 0.25mm lead frame, Package Outline . . . . . . . . . . . . . . . . . 33
Table 23. PDIP8 – 8 pin Plastic DIP, 0.25mm lead frame, Package Mechanical Data . . . . . . . . . . 33
Figure 20.SO8 narrow – 8 lead Plastic Small Outline, 150 mils body width, Package Outline . . . . 34
Table 24. SO8 narrow – 8 lead Plastic Small Outline, 150 mils body width, Package Mechanical Data
34
Figure 21.SO8 wide – 8 lead Plastic Small Outline, 200 mils body width, Package Outline . . . . . . 35
Table 25. SO8 wide – 8 lead Plastic Small Outline, 200 mils body width, Package Mechanical Data
35
Figure 22.TSSOP8 – 8 lead Thin Shrink Small Outline, Package Outline . . . . . . . . . . . . . . . . . . . 36
Table 26. TSSOP8 – 8 lead Thin Shrink Small Outline, Package Mechanical Data . . . . . . . . . . . . 36
PART NUMBERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Table 27. Ordering Information Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
REVISION HISTORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Table 28. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4/39
M95256, M95128
SUMMARY DESCRIPTION
Figure 3. DIP, SO and TSSOP Connections
These electrically erasable programmable memory (EEPROM) devices are accessed by a high
speed SPI-compatible bus. The memory array is
organized as 32768 x 8 bit (M95256) and 16384 x
8 bit (M95128).
The device is accessed by a simple serial interface
that is SPI-compatible. The bus signals are C, D
and Q, as shown in Table 2. and Figure 2..
The device is selected when Chip Select (S) is taken Low. Communications with the device can be
interrupted using Hold (HOLD).
M95xxx
S
Q
W
VSS
1
2
3
4
8
7
6
5
VCC
HOLD
C
D
AI01790D
Figure 2. Logic Diagram
Note: See PACKAGE MECHANICAL section for package dimensions, and how to identify pin-1.
VCC
Table 2. Signal Names
D
Q
C
S
M95xxx
C
Serial Clock
D
Serial Data Input
Q
Serial Data Output
S
Chip Select
W
Write Protect
HOLD
Hold
VCC
Supply Voltage
VSS
Ground
W
HOLD
VSS
AI01789C
5/39
M95256, M95128
SIGNAL DESCRIPTION
During all operations, V CC 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, as specified in Table 13. to Table 17.).
These signals are described next.
Serial Data Output (Q). This output signal is
used to transfer data serially out of the device.
Data is shifted out on the falling edge of Serial
Clock (C).
Serial Data Input (D). This input signal is used to
transfer data serially into the device. It receives instructions, addresses, and the data to be written.
Values are latched on the rising edge of Serial
Clock (C).
Serial Clock (C). This input signal provides the
timing of the serial interface. Instructions, addresses, or data present at Serial Data Input (D) are
latched on the rising edge of Serial Clock (C). Data
on Serial Data Output (Q) changes after the falling
edge of Serial Clock (C).
Chip Select (S). When this input signal is High,
the device is deselected and Serial Data Output
6/39
(Q) is at high impedance. Unless an internal Write
cycle is in progress, the device will be in the Standby Power mode. Driving Chip Select (S) Low selects the device, placing it in the Active Power
mode.
After Power-up, a falling edge on Chip Select (S)
is required prior to the start of any instruction.
Hold (HOLD). The Hold (HOLD) signal is used to
pause any serial communications with the device
without deselecting the device.
During the Hold condition, the Serial Data Output
(Q) is high impedance, and Serial Data Input (D)
and Serial Clock (C) are Don’t Care.
To start the Hold condition, the device must be selected, with Chip Select (S) driven Low.
Write Protect (W). The main purpose of this input signal is to freeze the size of the area of memory that is protected against Write instructions (as
specified by the values in the BP1 and BP0 bits of
the Status Register).
This pin must be driven either High or Low, and
must be stable during all write instructions.
M95256, M95128
CONNECTING TO THE SPI BUS
These devices are fully compatible with the SPI
protocol.
All instructions, addresses and input data bytes
are shifted in to the device, most significant bit
first. The Serial Data Input (D) is sampled on the
first rising edge of the Serial Clock (C) after Chip
Select (S) goes Low.
All output data bytes are shifted out of the device,
most significant bit first. The Serial Data Output
(Q) is latched on the first falling edge of the Serial
Clock (C) after the instruction (such as the Read
from Memory Array and Read Status Register instructions) have been clocked into the device.
Figure 4. shows three devices, connected to an
MCU, on a SPI bus. Only one device is selected at
a time, so only one device drives the Serial Data
Output (Q) line at a time, all the others being high
impedance.
Figure 4. Bus Master and Memory Devices on the SPI Bus
SDO
SPI Interface with
(CPOL, CPHA) =
(0, 0) or (1, 1)
SDI
SCK
C Q D
C Q D
C Q D
SPI Memory
Device
SPI Memory
Device
SPI Memory
Device
Bus Master
(ST6, ST7, ST9,
ST10, Others)
CS3
CS2
CS1
S
W
HOLD
S
W
HOLD
S
W
HOLD
AI03746D
Note: The Write Protect (W) and Hold (HOLD) signals should be driven, High or Low as appropriate.
7/39
M95256, M95128
SPI Modes
These devices can be driven by a microcontroller
with its SPI peripheral running in either of the two
following modes:
– CPOL=0, CPHA=0
– CPOL=1, CPHA=1
For these two modes, input data is latched in on
the rising edge of Serial Clock (C), and output data
is available from the falling edge of Serial Clock
(C).
The difference between the two modes, as shown
in Figure 5., is the clock polarity when the bus
master is in Stand-by mode and not transferring
data:
– C remains at 0 for (CPOL=0, CPHA=0)
– C remains at 1 for (CPOL=1, CPHA=1)
Figure 5. SPI Modes Supported
CPOL
CPHA
0
0
C
1
1
C
D
Q
MSB
MSB
AI01438B
8/39
M95256, M95128
OPERATING FEATURES
Power-up
When the power supply is turned on, V CC rises
from VSS to VCC.
During this time, the Chip Select (S) must be allowed to follow the V CC voltage. It must not be allowed to float, but should be connected to VCC via
a suitable pull-up resistor.
As a built in safety feature, Chip Select (S) is edge
sensitive as well as level sensitive. After Powerup, the device does not become selected until a
falling edge has first been detected on Chip Select
(S). This ensures that Chip Select (S) must have
been High, prior to going Low to start the first operation.
Power On Reset: V CC Lock-Out Write Protect
In order to prevent data corruption and inadvertent
Write instructions during Power-up, a Power On
Reset (POR) circuit is included. The internal reset
is held active until V CC has reached the Power On
Reset (POR) threshold voltage, and all operations
are disabled – the device will not respond to any
instruction. In the same way, when VCC drops from
the operating voltage, below the Power On Reset
(POR) threshold voltage, all operations are disabled and the device will not respond to any instruction.
A stable and valid VCC must be applied before applying any logic signal.
Power-down
At Power-down, the device must be deselected.
Chip Select (S) should be allowed to follow the
voltage applied on V CC.
Active Power and Standby Power Modes
When Chip Select (S) is Low, the device is selected, and in the Active Power mode. The device
consumes ICC, as specified in Table 13. to Table
17..
When Chip Select (S) is High, the device is deselected. If an Erase/Write cycle is not currently in
progress, the device then goes in to the Standby
Power mode, and the device consumption drops
to ICC1.
Hold Condition
The Hold (HOLD) signal is used to pause any serial communications with the device without resetting the clocking sequence.
During the Hold condition, the Serial Data Output
(Q) is high impedance, and Serial Data Input (D)
and Serial Clock (C) are Don’t Care.
To enter the Hold condition, the device must be
selected, with Chip Select (S) Low.
Normally, the device is kept selected, for the whole
duration of the Hold condition. Deselecting the device while it is in the Hold condition, has the effect
of resetting the state of the device, and this mechanism can be used if it is required to reset any processes that had been in progress.
The Hold condition starts when the Hold (HOLD)
signal is driven Low at the same time as Serial
Clock (C) already being Low (as shown in Figure
6.).
The Hold condition ends when the Hold (HOLD)
signal is driven High at the same time as Serial
Clock (C) already being Low.
Figure 6. also shows what happens if the rising
and falling edges are not timed to coincide with
Serial Clock (C) being Low.
Figure 6. Hold Condition Activation
C
HOLD
Hold
Condition
Hold
Condition
AI02029D
9/39
M95256, M95128
Status Register
Figure 7. shows the position of the Status Register
in the control logic of the device. 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 or Write
Status Register cycle.
WEL bit. The Write Enable Latch (WEL) bit indicates the status of the internal Write Enable Latch.
BP1, BP0 bits. The Block Protect (BP1, BP0) bits
are non-volatile. They define the size of the area to
be software protected against Write instructions.
SRWD bit. The Status Register Write Disable
(SRWD) bit is operated in conjunction with the
Write Protect (W) signal. The Status Register
Write Disable (SRWD) bit and Write Protect (W)
signal allow the device to be put in the Hardware
Protected mode. In this mode, the non-volatile bits
of the Status Register (SRWD, BP1, BP0) become
read-only bits.
device features the following data protection
mechanisms:
■
Write 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.
■
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
– Write Status Register (WRSR) instruction
completion
– Write (WRITE) instruction completion
■
The Block Protect (BP1, BP0) bits allow part of
the memory to be configured as read-only.
This is the Software Protected Mode (SPM).
■
The Write Protect (W) signal allows the Block
Protect (BP1, BP0) bits to be protected. This is
the Hardware Protected Mode (HPM).
For any instruction to be accepted, and executed,
Chip Select (S) must be driven High after the rising
edge of Serial Clock (C) for the last bit of the instruction, and before the next rising edge of Serial
Clock (C).
Two points need to be noted in the previous sentence:
– The ‘last bit of the instruction’ can be the
eighth bit of the instruction code, or the eighth
bit of a data byte, depending on the instruction
(except for Read Status Register (RDSR) and
Read (READ) instructions).
– The ‘next rising edge of Serial Clock (C)’ might
(or might not) be the next bus transaction for
some other device on the SPI bus.
Table 3. Status Register Format
b7
SRWD
b0
0
0
0
BP1
BP0
WEL
WIP
Status Register Write Protect
Block Protect Bits
Write Enable Latch Bit
Write In Progress Bit
Data Protection and Protocol Control
Non-volatile memory devices can be used in environments that are particularly noisy, and within applications that could experience problems if
memory bytes are corrupted. Consequently, the
Table 4. Write-Protected Block Size
Status Register Bits
Array Addresses Protected
Protected Block
10/39
BP1
BP0
M95256
M95128
0
0
none
none
none
0
1
Upper quarter
6000h - 7FFFh
3000h - 3FFFh
1
0
Upper half
4000h - 7FFFh
2000h - 3FFFh
1
1
Whole memory
0000h - 7FFFh
0000h - 3FFFh
M95256, M95128
MEMORY ORGANIZATION
The memory is organized as shown in Figure 7..
Figure 7. Block Diagram
HOLD
W
High Voltage
Generator
Control Logic
S
C
D
I/O Shift Register
Q
Address Register
and Counter
Data
Register
Size of the
Read only
EEPROM
area
Y Decoder
Status
Register
1 Page
X Decoder
AI01272C
11/39
M95256, M95128
INSTRUCTIONS
Each instruction starts with a single-byte code, as
summarized in Table 5..
If an invalid instruction is sent (one not contained
in Table 5.), the device automatically deselects itself.
12/39
Table 5. Instruction Set
Instruc
tion
Description
Instruction
Format
WREN
Write Enable
0000 0110
WRDI
Write Disable
0000 0100
RDSR
Read Status Register
0000 0101
WRSR
Write Status Register
0000 0001
READ
Read from Memory Array
0000 0011
WRITE
Write to Memory Array
0000 0010
M95256, M95128
Write Enable (WREN)
The Write Enable Latch (WEL) bit must be set prior to each WRITE and WRSR instruction. The only
way to do this is to send a Write Enable instruction
to the device.
As shown in Figure 8., to send this instruction to
the device, Chip Select (S) is driven Low, and the
bits of the instruction byte are shifted in, on Serial
Data Input (D). The device then enters a wait
state. It waits for a the device to be deselected, by
Chip Select (S) being driven High.
Figure 8. Write Enable (WREN) Sequence
S
0
1
2
3
4
5
6
7
C
Instruction
D
High Impedance
Q
AI02281E
Write Disable (WRDI)
One way of resetting the Write Enable Latch
(WEL) bit is to send a Write Disable instruction to
the device.
As shown in Figure 9., to send this instruction to
the device, Chip Select (S) is driven Low, and the
bits of the instruction byte are shifted in, on Serial
Data Input (D).
The device then enters a wait state. It waits for a
the device to be deselected, by Chip Select (S) being driven High.
The Write Enable Latch (WEL) bit, in fact, becomes reset by any of the following events:
– Power-up
– WRDI instruction execution
– WRSR instruction completion
– WRITE instruction completion.
Figure 9. Write Disable (WRDI) Sequence
S
0
1
2
3
4
5
6
7
C
Instruction
D
High Impedance
Q
AI03750D
13/39
M95256, M95128
Read Status Register (RDSR)
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
Write 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 10..
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 or Write
Status Register 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 or Write Status Register instruction is accepted.
BP1, BP0 bits. The Block Protect (BP1, BP0) bits
are non-volatile. They define the size of the area to
be software protected against Write instructions.
These bits are written with the Write Status Register (WRSR) instruction. When one or both of the
Block Protect (BP1, BP0) bits is set to 1, the relevant memory area (as defined in Table 3.) becomes protected against Write (WRITE)
instructions. The Block Protect (BP1, BP0) bits
can be written provided that the Hardware Protected mode has not been set.
SRWD bit. The Status Register Write Disable
(SRWD) bit is operated in conjunction with the
Write Protect (W) signal. The Status Register
Write Disable (SRWD) bit and Write Protect (W)
signal allow the device to be put in the Hardware
Protected mode (when the Status Register Write
Disable (SRWD) bit is set to 1, and Write Protect
(W) is driven Low). In this mode, the non-volatile
bits of the Status Register (SRWD, BP1, BP0) become read-only bits and the Write Status Register
(WRSR) instruction is no longer accepted for execution.
Figure 10. Read Status Register (RDSR) Sequence
S
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
C
Instruction
D
Status Register Out
Status Register Out
High Impedance
Q
7
MSB
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
7
MSB
AI02031E
14/39
M95256, M95128
Write Status Register (WRSR)
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 (S) Low, followed
by the instruction code and the data byte on Serial
Data Input (D).
The instruction sequence is shown in Figure 11..
The Write Status Register (WRSR) instruction has
no effect on b6, b5, b4, b1 and b0 of the Status
Register. b6, b5 and b4 are always read as 0.
Chip Select (S) must be driven High after the rising
edge of Serial Clock (C) that latches in the eighth
bit of the data byte, and before the next rising edge
of Serial Clock (C). Otherwise, the Write Status
Register (WRSR) instruction is not executed. As
soon as Chip Select (S) is driven High, the selftimed 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 (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
Write Disable (SRWD) bit in accordance with the
Write Protect (W) signal. The Status Register
Write Disable (SRWD) bit and Write Protect (W)
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.
The contents of the Status Register Write Disable
(SRWD) and Block Protect (BP1, BP0) bits are frozen at their current values from just before the
start of the execution of Write Status Register
(WRSR) instruction. The new, updated, values
take effect at the moment of completion of the execution of Write Status Register (WRSR) instruction.
Table 6. Protection Modes
W
Signal
SRWD
Bit
1
0
0
0
1
1
0
1
Memory Content
Mode
Write Protection of the
Status Register
Software
Protected
(SPM)
Status Register is Writable
(if the WREN instruction
has set the WEL bit)
The values in the BP1 and
BP0 bits can be changed
Write Protected
Ready to accept Write
instructions
Hardware
Protected
(HPM)
Status Register is
Hardware write protected
The values in the BP1 and
BP0 bits cannot be
changed
Write Protected
Ready to accept Write
instructions
Protected Area1
Unprotected Area1
Note: 1. As defined by the values in the Block Protect (BP1, BP0) bits of the Status Register, as shown in Table 6..
The protection features of the device are summarized in Table 4..
When the Status Register Write Disable (SRWD)
bit of the Status Register is 0 (its initial delivery
state), it is possible to write to the Status Register
provided that the Write Enable Latch (WEL) bit has
previously been set by a Write Enable (WREN) instruction, regardless of the whether Write Protect
(W) is driven High or Low.
When the Status Register Write Disable (SRWD)
bit of the Status Register is set to 1, two cases
need to be considered, depending on the state of
Write Protect (W):
–
–
If Write Protect (W) is driven High, it is
possible to write to the Status Register
provided that the Write Enable Latch (WEL) bit
has previously been set by a Write Enable
(WREN) instruction.
If Write Protect (W) is driven Low, it is not
possible to write to the Status Register even if
the Write Enable Latch (WEL) bit has
previously been set by a Write Enable
(WREN) instruction. (Attempts to write to the
Status Register are rejected, and are not
accepted for execution). As a consequence,
all the data bytes in the memory area that are
software protected (SPM) by the Block Protect
15/39
M95256, M95128
(BP1, BP0) bits of the Status Register, are
also hardware protected against data
modification.
Regardless of the order of the two events, the
Hardware Protected Mode (HPM) can be entered:
– by setting the Status Register Write Disable
(SRWD) bit after driving Write Protect (W) Low
– or by driving Write Protect (W) Low after
setting the Status Register Write Disable
(SRWD) bit.
The only way to exit the Hardware Protected Mode
(HPM) once entered is to pull Write Protect (W)
High.
If Write Protect (W) is permanently tied High, the
Hardware Protected Mode (HPM) can never be
activated, and only the Software Protected Mode
(SPM), using the Block Protect (BP1, BP0) bits of
the Status Register, can be used.
Figure 11. Write Status Register (WRSR) Sequence
S
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
C
Instruction
Status
Register In
7
D
High Impedance
6
5
4
3
2
1
0
MSB
Q
AI02282D
16/39
M95256, M95128
Read from Memory Array (READ)
As shown in Figure 12., to send this instruction to
the device, Chip Select (S) is first driven Low. The
bits of the instruction byte and address bytes are
then shifted in, on Serial Data Input (D). The address is loaded into an internal address register,
and the byte of data at that address is shifted out,
on Serial Data Output (Q).
If Chip Select (S) continues to be driven Low, the
internal address register is automatically incremented, and the byte of data at the new address is
shifted out.
When the highest address is reached, the address
counter rolls over to zero, allowing the Read cycle
to be continued indefinitely. The whole memory
can, therefore, be read with a single READ instruction.
The Read cycle is terminated by driving Chip Select (S) High. The rising edge of the Chip Select
(S) signal can occur at any time during the cycle.
The first byte addressed can be any byte within
any page.
The instruction is not accepted, and is not executed, if a Write cycle is currently in progress.
Figure 12. Read from Memory Array (READ) Sequence
S
0
1
2
3
4
5
6
7
8
9 10
20 21 22 23 24 25 26 27 28 29 30 31
C
Instruction
16-Bit Address
15 14 13
D
3
2
1
0
MSB
Data Out 1
High Impedance
Q
7
6
5
4
3
2
Data Out 2
1
0
7
MSB
AI01793D
Note: The most significant address bits (b15 for the M95256, and bits b15 and b14 for the M95128) are Don’t Care.
17/39
M95256, M95128
Write to Memory Array (WRITE)
As shown in Figure 13., to send this instruction to
the device, Chip Select (S) is first driven Low. The
bits of the instruction byte, address byte, and at
least one data byte are then shifted in, on Serial
Data Input (D).
The instruction is terminated by driving Chip Select (S) High at a byte boundary of the input data.
In the case of Figure 13., this occurs after the
eighth bit of the data byte has been latched in, indicating that the instruction is being used to write
a single byte. The self-timed Write cycle starts,
and continues for a period tWC (as specified in Table 18. to Table 22.), at the end of which the Write
in Progress (WIP) bit is reset to 0.
If, though, Chip Select (S) continues to be driven
Low, as shown in Figure 14., the next byte of input
data is shifted in, so that more than a single byte,
starting from the given address towards the end of
the same page, can be written in a single internal
Write cycle.
Each time a new data byte is shifted in, the least
significant bits of the internal address counter are
incremented. If the number of data bytes sent to
the device exceeds the page boundary, the internal address counter rolls over to the beginning of
the page, and the previous data there are overwritten with the incoming data. (The page size of
these devices is 64 bytes).
The instruction is not accepted, and is not executed, under the following conditions:
– if the Write Enable Latch (WEL) bit has not
been set to 1 (by executing a Write Enable
instruction just before)
– if a Write cycle is already in progress
– if the device has not been deselected, by Chip
Select (S) being driven High, at a byte
boundary (after the eighth bit, b0, of the last
data byte that has been latched in)
– if the addressed page is in the region
protected by the Block Protect (BP1 and BP0)
bits.
Figure 13. Byte Write (WRITE) Sequence
S
0
1
2
3
4
5
6
7
8
9 10
20 21 22 23 24 25 26 27 28 29 30 31
C
Instruction
16-Bit Address
15 14 13
D
3
2
Data Byte
1
0
7
6
5
4
3
2
1
0
High Impedance
Q
AI01795D
Note: The most significant address bits (b15 for the M95256, and bits b15 and b14 for the M95128) are Don’t Care.
18/39
M95256, M95128
Figure 14. Page Write (WRITE) Sequence
S
0
1
2
3
4
5
6
7
8
20 21 22 23 24 25 26 27 28 29 30 31
9 10
C
Instruction
16-Bit Address
15 14 13
D
3
2
Data Byte 1
1
0
7
6
5
4
3
2
0
1
S
32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
C
Data Byte 2
D
7
6
5
4
3
2
Data Byte 3
1
0
7
6
5
4
3
2
Data Byte N
1
0
6
5
4
3
2
1
0
AI01796D
Note: The most significant address bits (b15 for the M95256, and bits b15 and b14 for the M95128) are Don’t Care.
19/39
M95256, M95128
POWER-UP AND DELIVERY STATE
Power-up State
After Power-up, the device is in the following state:
– Standby Power mode
– deselected (after Power-up, a falling edge is
required on Chip Select (S) before any
instructions can be started).
– not in the Hold Condition
– the Write Enable Latch (WEL) is reset to 0
– Write In Progress (WIP) is reset to 0
The SRWD, BP1 and BP0 bits of the Status Register are unchanged from the previous powerdown (they are non-volatile bits).
20/39
Initial Delivery State
The device is delivered with the memory array set
at all 1s (FFh). The Status Register Write Disable
(SRWD) and Block Protect (BP1 and BP0) bits are
initialized to 0.
M95256, M95128
MAXIMUM RATING
Stressing the device outside the ratings listed in
Table 7. may cause permanent damage to the device. These are stress ratings only, and operation
of the device at these, or any other conditions outside those indicated in the Operating sections of
this specification, is not implied. Exposure to Absolute Maximum Rating conditions for extended
periods may affect device reliability. Refer also to
the STMicroelectronics SURE Program and other
relevant quality documents.
Table 7. Absolute Maximum Ratings
Symbol
Parameter
TSTG
Storage Temperature
TLEAD
Lead Temperature during Soldering
Min.
Max.
Unit
–65
150
°C
See note 1
°C
VO
Output Voltage
–0.50
VCC+0.6
V
VI
Input Voltage
–0.50
6.5
V
VCC
Supply Voltage
–0.50
6.5
V
VESD
Electrostatic Discharge Voltage (Human Body model) 2
–4000
4000
V
Note: 1. Compliant with JEDEC Std J-STD-020B (for small body, Sn-Pb or Pb assembly), the ST ECOPACK ® 7191395 specification, and
the European directive on Restrictions on Hazardous Substances (RoHS) 2002/95/EU
2. AEC-Q100-002 (compliant with JEDEC Std JESD22-A114A, C1=100pF, R1=1500Ω, R2=500Ω)
21/39
M95256, M95128
DC AND AC PARAMETERS
This section summarizes the operating and measurement conditions, and the DC and AC characteristics of the device. The parameters in the DC
and AC Characteristic tables that follow are derived from tests performed under the Measure-
ment Conditions summarized in the relevant
tables. Designers should check that the operating
conditions in their circuit match the measurement
conditions when relying on the quoted parameters.
Table 8. Operating Conditions (M95xxx)
Symbol
VCC
Parameter
Min.
Max.
Unit
Supply Voltage
4.5
5.5
V
Ambient Operating Temperature (Device Grade 6)
–40
85
°C
Ambient Operating Temperature (Device Grade 3)
–40
125
°C
Min.
Max.
Unit
Supply Voltage
2.5
5.5
V
Ambient Operating Temperature (Device Grade 6)
–40
85
°C
Ambient Operating Temperature (Device Grade 3)1
–40
125
°C
TA
Table 9. Operating Conditions (M95xxx-W)
Symbol
VCC
TA
Parameter
Note: 1. This product is under development. For more information, please contact your nearest ST sales office.
Table 10. Operating Conditions (M95xxx-R)
Min. 1
Max. 1
Unit
Supply Voltage
1.8
5.5
V
Ambient Operating Temperature
–40
85
°C
Symbol
VCC
TA
Parameter
Note: 1. This product is under development. For more information, please contact your nearest ST sales office.
22/39
M95256, M95128
Table 11. AC Measurement Conditions
Symbol
CL
Parameter
Min.
Load Capacitance
Max.
100
Input Rise and Fall Times
Unit
pF
50
ns
Input Pulse Voltages
0.2VCC to 0.8VCC
V
Input and Output Timing Reference Voltages
0.3VCC to 0.7VCC
V
Note: Output Hi-Z is defined as the point where data out is no longer driven.
Figure 15. AC Measurement I/O Waveform
Input Levels
Input and Output
Timing Reference Levels
0.8VCC
0.7VCC
0.3VCC
0.2VCC
AI00825B
Table 12. Capacitance
Symbol
COUT
CIN
Parameter
Max.
Unit
VOUT = 0V
8
pF
Input Capacitance (D)
VIN = 0V
8
pF
Input Capacitance (other pins)
VIN = 0V
6
pF
Output Capacitance (Q)
Test Condition
Min.
Note: Sampled only, not 100% tested, at TA=25°C and a frequency of 5 MHz.
23/39
M95256, M95128
Table 13. DC Characteristics (M95xxx, Device Grade 6)
Symbol
Parameter
Test Condition
Min.
Max.
Unit
VIN = VSS or VCC
±2
µA
S = VCC, VOUT = VSS or VCC
±2
µA
C = 0.1VCC/0.9VCC at 10MHz,
VCC = 5 V, Q = open
5
mA
S = VCC , VCC = 5 V,
VIN = VSS or VCC
2
µA
ILI
Input Leakage Current
ILO
Output Leakage Current
ICC
Supply Current
ICC1
Supply Current
(Standby Power mode)
VIL
Input Low Voltage
–0.45
0.3 VCC
V
VIH
Input High Voltage
0.7 VCC
VCC+1
V
VOL1
Output Low Voltage
IOL = 2 mA, VCC = 5 V
0.4
V
VOH1
Output High Voltage
IOH = –2 mA, VCC = 5 V
0.8 VCC
V
Note: 1. For all 5V range devices, the device meets the output requirements for both TTL and CMOS standards.
Table 14. DC Characteristics (M95xxx, Device Grade 3)
Symbol
Parameter
Test Condition
Min.
Max.
Unit
VIN = VSS or VCC
±2
µA
S = VCC, VOUT = VSS or VCC
±2
µA
C = 0.1VCC/0.9VCC at 5 MHz,
VCC = 5 V, Q = open
4
mA
S = VCC , VCC = 5 V,
VIN = VSS or VCC
5
µA
ILI
Input Leakage Current
ILO
Output Leakage Current
ICC
Supply Current
ICC1
Supply Current
(Standby Power mode)
VIL
Input Low Voltage
–0.45
0.3 VCC
V
VIH
Input High Voltage
0.7 VCC
VCC+1
V
VOL1
Output Low Voltage
IOL = 2 mA, VCC = 5 V
0.4
V
VOH1
Output High Voltage
IOH = –2 mA, VCC = 5 V
0.8 VCC
V
Note: 1. For all 5V range devices, the device meets the output requirements for both TTL and CMOS standards.
Table 15. DC Characteristics (M95xxx-W, Device Grade 6)
Symbol
Parameter
Test Condition
Min.
Max.
Unit
VIN = VSS or VCC
±2
µA
S = VCC, VOUT = VSS or VCC
±2
µA
C = 0.1VCC/0.9VCC at 5 MHz,
VCC = 2.5 V, Q = open
3
mA
S = VCC , VCC = 2.5 V
VIN = VSS or VCC
1
µA
ILI
Input Leakage Current
ILO
Output Leakage Current
ICC
Supply Current
ICC1
Supply Current
(Standby Power mode)
VIL
Input Low Voltage
–0.45
0.3 VCC
V
VIH
Input High Voltage
0.7 VCC
VCC+1
V
VOL
Output Low Voltage
IOL = 1.5 mA, VCC = 2.5 V
0.4
V
VOH
Output High Voltage
IOH = –0.4 mA, VCC = 2.5 V
24/39
0.8 VCC
V
M95256, M95128
Table 16. DC Characteristics (M95xxx-W, Device Grade 3)
Symbol
Parameter
Max.
Unit
VIN = VSS or VCC
±2
µA
S = VCC, VOUT = VSS or VCC
±2
µA
C = 0.1VCC/0.9VCC at 5 MHz,
VCC = 2.5 V, Q = open
3
mA
S = VCC , VCC = 2.5 V, VIN = VSS or VCC
2
µA
Test Condition
Min.
ILI
Input Leakage Current
ILO
Output Leakage Current
ICC
Supply Current
ICC1
Supply Current
(Standby Power mode)
VIL
Input Low Voltage
–0.45
0.3 VCC
V
VIH
Input High Voltage
0.7 VCC
VCC+1
V
VOL
Output Low Voltage
IOL = 1.5 mA, VCC = 2.5 V
0.4
V
VOH
Output High Voltage
IOH = –0.4 mA, VCC = 2.5 V
0.8 VCC
V
Table 17. DC Characteristics (M95xxx-R)
Symbol
Parameter
Max.1
Unit
VIN = VSS or VCC
±2
µA
S = VCC, VOUT = VSS or VCC
±2
µA
C = 0.1VCC/0.9VCC at 2 MHz,
VCC = 1.8 V, Q = open
12
mA
S = VCC, VIN = VSS or VCC , VCC = 1.8 V
0.5 2
µA
Test Condition
Min.1
ILI
Input Leakage Current
ILO
Output Leakage Current
ICC
Supply Current
ICC1
Supply Current
(Standby Power mode)
VIL
Input Low Voltage
–0.45
0.25 VCC
V
VIH
Input High Voltage
0.7 VCC
VCC+1
V
VOL
Output Low Voltage
IOL = 0.15 mA, VCC = 1.8 V
0.3
V
VOH
Output High Voltage
IOH = –0.1 mA, VCC = 1.8 V
0.8 VCC
V
Note: 1. This product is under development. For more infomation, please contact your nearest ST sales office.
2. This is preliminary data.
25/39
M95256, M95128
Table 18. AC Characteristics (M95xxx, Device Grade 6)
Test conditions specified in Table 11. and Table 8.
Symbol
Alt.
fC
fSCK
Clock Frequency
tSLCH
tCSS1
S Active Setup Time
15
ns
tSHCH
tCSS2
S Not Active Setup Time
15
ns
tSHSL
tCS
S Deselect Time
40
ns
tCHSH
tCSH
S Active Hold Time
25
ns
S Not Active Hold Time
15
ns
tCHSL
Parameter
Min.
Max.
Unit
D.C.
10
MHz
tCH 1
tCLH
Clock High Time
40
ns
tCL 1
tCLL
Clock Low Time
40
ns
tCLCH 2
tRC
Clock Rise Time
1
µs
tCHCL 2
tFC
Clock Fall Time
1
µs
tDVCH
tDSU
Data In Setup Time
15
ns
tCHDX
tDH
Data In Hold Time
15
ns
tHHCH
Clock Low Hold Time after HOLD not Active
15
ns
tHLCH
Clock Low Hold Time after HOLD Active
20
ns
tCHHL
Clock High Set-up Time before HOLD Active
30
ns
tCHHH
Clock High Set-up Time before HOLD not
Active
30
ns
tSHQZ 2
tDIS
tCLQV
tV
tCLQX
tHO
Output Hold Time
tQLQH 2
tRO
Output Rise Time
20
ns
tQHQL 2
tFO
Output Fall Time
20
ns
tHHQV
tLZ
HOLD High to Output Valid
25
ns
tHLQZ 2
tHZ
HOLD Low to Output High-Z
25
ns
tW
tWC
Write Time
5
ms
Output Disable Time
25
ns
Clock Low to Output Valid
25
ns
Note: 1. tCH + tCL must never be less than the shortest possible clock period, 1 / fC(max)
2. Value guaranteed by characterization, not 100% tested in production.
26/39
0
ns
M95256, M95128
Table 19. AC Characteristics (M95xxx, Device Grade 3)
Test conditions specified in Table 11. and Table 8.
Symbol
Alt.
fC
fSCK
Clock Frequency
tSLCH
tCSS1
S Active Setup Time
90
ns
tSHCH
tCSS2
S Not Active Setup Time
90
ns
tSHSL
tCS
S Deselect Time
100
ns
tCHSH
tCSH
S Active Hold Time
90
ns
S Not Active Hold Time
90
ns
tCHSL
Parameter
Min.
Max.
Unit
D.C.
5
MHz
tCH 1
tCLH
Clock High Time
90
ns
tCL 1
tCLL
Clock Low Time
90
ns
tCLCH 2
tRC
Clock Rise Time
1
µs
tCHCL 2
tFC
Clock Fall Time
1
µs
tDVCH
tDSU
Data In Setup Time
20
ns
tCHDX
tDH
Data In Hold Time
30
ns
tHHCH
Clock Low Hold Time after HOLD not Active
70
ns
tHLCH
Clock Low Hold Time after HOLD Active
40
ns
tCHHL
Clock High Set-up Time before HOLD Active
60
ns
tCHHH
Clock High Set-up Time before HOLD not
Active
60
ns
tSHQZ 2
tDIS
tCLQV
tV
tCLQX
tHO
Output Hold Time
tQLQH 2
tRO
Output Rise Time
50
ns
tQHQL 2
tFO
Output Fall Time
50
ns
tHHQV
tLZ
HOLD High to Output Valid
50
ns
tHLQZ 2
tHZ
HOLD Low to Output High-Z
100
ns
tW
tWC
Write Time
5
ms
Output Disable Time
100
ns
Clock Low to Output Valid
60
ns
0
ns
Note: 1. tCH + tCL must never be less than the shortest possible clock period, 1 / fC(max)
2. Value guaranteed by characterization, not 100% tested in production.
27/39
M95256, M95128
Table 20. AC Characteristics (M95xxx-W, Device Grade 6)
Test conditions specified in Table 11. and Table 9.
Symbol
Alt.
fC
fSCK
Clock Frequency
tSLCH
tCSS1
S Active Setup Time
90
ns
tSHCH
tCSS2
S Not Active Setup Time
90
ns
tSHSL
tCS
S Deselect Time
100
ns
tCHSH
tCSH
S Active Hold Time
90
ns
S Not Active Hold Time
90
ns
tCHSL
Parameter
Min.
Max.
Unit
D.C.
5
MHz
tCH 1
tCLH
Clock High Time
90
ns
tCL 1
tCLL
Clock Low Time
90
ns
tCLCH 2
tRC
Clock Rise Time
1
µs
tCHCL 2
tFC
Clock Fall Time
1
µs
tDVCH
tDSU
Data In Setup Time
20
ns
tCHDX
tDH
Data In Hold Time
30
ns
tHHCH
Clock Low Hold Time after HOLD not Active
70
ns
tHLCH
Clock Low Hold Time after HOLD Active
40
ns
tCHHL
Clock High Set-up Time before HOLD Active
60
ns
tCHHH
Clock High Set-up Time before HOLD not
Active
60
ns
tSHQZ 2
tDIS
tCLQV
tV
tCLQX
tHO
Output Hold Time
tQLQH 2
tRO
Output Rise Time
50
ns
tQHQL 2
tFO
Output Fall Time
50
ns
tHHQV
tLZ
HOLD High to Output Valid
50
ns
tHLQZ 2
tHZ
HOLD Low to Output High-Z
100
ns
tW
tWC
Write Time
5
ms
Output Disable Time
100
ns
Clock Low to Output Valid
60
ns
Note: 1. tCH + tCL must never be less than the shortest possible clock period, 1 / fC(max)
2. Value guaranteed by characterization, not 100% tested in production.
28/39
0
ns
M95256, M95128
Table 21. AC Characteristics (M95xxx-W, Device Grade 3)
Test conditions specified in Table 11. and Table 9.
Symbol
Alt.
fC
fSCK
Clock Frequency
tSLCH
tCSS1
S Active Setup Time
90
ns
tSHCH
tCSS2
S Not Active Setup Time
90
ns
tSHSL
tCS
S Deselect Time
100
ns
tCHSH
tCSH
S Active Hold Time
90
ns
S Not Active Hold Time
90
ns
tCHSL
Parameter
Min.
Max.
Unit
D.C.
5
MHz
tCH 1
tCLH
Clock High Time
90
ns
tCL 1
tCLL
Clock Low Time
90
ns
tCLCH 2
tRC
Clock Rise Time
1
µs
tCHCL 2
tFC
Clock Fall Time
1
µs
tDVCH
tDSU
Data In Setup Time
20
ns
tCHDX
tDH
Data In Hold Time
30
ns
tHHCH
Clock Low Hold Time after HOLD not Active
70
ns
tHLCH
Clock Low Hold Time after HOLD Active
40
ns
tCHHL
Clock High Set-up Time before HOLD Active
tCH
ns
tCHHH
Clock High Set-up Time before HOLD not Active
tCH
ns
tSHQZ 2
tDIS
tCLQV
tV
tCLQX
tHO
Output Hold Time
tQLQH 2
tRO
Output Rise Time
50
ns
tQHQL 2
tFO
Output Fall Time
50
ns
tHHQV
tLZ
HOLD High to Output Valid
50
ns
tHLQZ 2
tHZ
HOLD Low to Output High-Z
100
ns
tW
tWC
Write Time
5
ms
Output Disable Time
100
ns
Clock Low to Output Valid
60
ns
0
ns
Note: 1. tCH + tCL must never be less than the shortest possible clock period, 1 / fC(max)
2. Value guaranteed by characterization, not 100% tested in production.
29/39
M95256, M95128
Table 22. AC Characteristics (M95xxx-R)
Test conditions specified in Table 11. and Table 10.
Min.3,4
Max.3,4
Unit
Clock Frequency
D.C.
2
MHz
tCSS1
S Active Setup Time
200
ns
tSHCH
tCSS2
S Not Active Setup Time
200
ns
tSHSL
tCS
S Deselect Time
200
ns
tCHSH
tCSH
S Active Hold Time
200
ns
S Not Active Hold Time
200
ns
Symbol
Alt.
fC
fSCK
tSLCH
tCHSL
Parameter
tCH 1
tCLH
Clock High Time
200
ns
tCL 1
tCLL
Clock Low Time
200
ns
tCLCH 2
tRC
Clock Rise Time
1
µs
tCHCL 2
tFC
Clock Fall Time
1
µs
tDVCH
tDSU
Data In Setup Time
40
ns
tCHDX
tDH
Data In Hold Time
50
ns
tHHCH
Clock Low Hold Time after HOLD not Active
140
ns
tHLCH
Clock Low Hold Time after HOLD Active
90
ns
tCHHL
Clock High Set-up Time before HOLD Active
tCH
ns
tCHHH
Clock High Set-up Time before HOLD not Active
tCH
ns
tSHQZ 2
tDIS
tCLQV
tV
tCLQX
tHO
Output Hold Time
tQLQH 2
tRO
Output Rise Time
100
ns
tQHQL 2
tFO
Output Fall Time
100
ns
tHHQV
tLZ
HOLD High to Output Valid
100
ns
tHLQZ 2
tHZ
HOLD Low to Output High-Z
250
ns
tW
tWC
Write Time
10
ms
Note: 1.
2.
3.
4.
30/39
Output Disable Time
250
ns
Clock Low to Output Valid
150
ns
0
tCH + tCL must never be less than the shortest possible clock period, 1 / fC(max)
Value guaranteed by characterization, not 100% tested in production.
This product is under development. For more infomation, please contact your nearest ST sales office.
This is preliminary data.
ns
M95256, M95128
Figure 16. Serial Input Timing
tSHSL
S
tCHSL
tSLCH
tCHSH
tSHCH
C
tDVCH
tCHCL
tCHDX
D
Q
tCLCH
LSB IN
MSB IN
High Impedance
AI01447C
Figure 17. Hold Timing
S
tHLCH
tCHHL
tHHCH
C
tCHHH
tHLQZ
tHHQV
Q
D
HOLD
AI02032B
31/39
M95256, M95128
Figure 18. Output Timing
S
tCH
C
tCLQV
tCLQX
tCLQV
tCL
tSHQZ
tCLQX
LSB OUT
Q
tQLQH
tQHQL
D
ADDR.LSB IN
AI01449D
32/39
M95256, M95128
PACKAGE MECHANICAL
Figure 19. PDIP8 – 8 pin Plastic DIP, 0.25mm lead frame, Package Outline
E
b2
A2
A1
b
A
L
c
e
eA
eB
D
8
E1
1
PDIP-B
Note: Drawing is not to scale.
Table 23. PDIP8 – 8 pin Plastic DIP, 0.25mm lead frame, Package Mechanical Data
mm
inches
Symb.
Typ.
Min.
A
Max.
Typ.
Min.
5.33
A1
Max.
0.210
0.38
0.015
A2
3.30
2.92
4.95
0.130
0.115
0.195
b
0.46
0.36
0.56
0.018
0.014
0.022
b2
1.52
1.14
1.78
0.060
0.045
0.070
c
0.25
0.20
0.36
0.010
0.008
0.014
D
9.27
9.02
10.16
0.365
0.355
0.400
E
7.87
7.62
8.26
0.310
0.300
0.325
E1
6.35
6.10
7.11
0.250
0.240
0.280
e
2.54
–
–
0.100
–
–
eA
7.62
–
–
0.300
–
–
eB
L
10.92
3.30
2.92
3.81
0.430
0.130
0.115
0.150
33/39
M95256, M95128
Figure 20. SO8 narrow – 8 lead Plastic Small Outline, 150 mils body width, Package Outline
h x 45˚
A
C
B
CP
e
D
N
E
H
1
A1
α
L
SO-a
Note: Drawing is not to scale.
Table 24. SO8 narrow – 8 lead Plastic Small Outline, 150 mils body width, Package Mechanical Data
mm
inches
Symb.
Typ.
Min.
Max.
A
1.35
A1
Min.
Max.
1.75
0.053
0.069
0.10
0.25
0.004
0.010
B
0.33
0.51
0.013
0.020
C
0.19
0.25
0.007
0.010
D
4.80
5.00
0.189
0.197
E
3.80
4.00
0.150
0.157
–
–
–
–
H
5.80
6.20
0.228
0.244
h
0.25
0.50
0.010
0.020
L
0.40
0.90
0.016
0.035
α
0°
8°
0°
8°
N
8
e
CP
34/39
1.27
Typ.
0.050
8
0.10
0.004
M95256, M95128
Figure 21. SO8 wide – 8 lead Plastic Small Outline, 200 mils body width, Package Outline
A2
A
C
B
CP
e
D
N
E
H
1
A1
α
L
SO-b
Note: Drawing is not to scale.
Table 25. SO8 wide – 8 lead Plastic Small Outline, 200 mils body width, Package Mechanical Data
mm
inches
Symb.
Typ.
Min.
A
Max.
Typ.
Min.
2.03
A1
0.10
A2
0.080
0.25
0.004
1.78
B
0.35
0.45
–
–
D
5.15
E
Max.
0.010
0.070
0.014
0.018
–
–
5.35
0.203
0.211
5.20
5.40
0.205
0.213
–
–
–
–
H
7.70
8.10
0.303
0.319
L
0.50
0.80
0.020
0.031
α
0°
10°
0°
10°
N
8
C
e
CP
0.20
1.27
0.008
0.050
8
0.10
0.004
35/39
M95256, M95128
Figure 22. TSSOP8 – 8 lead Thin Shrink Small Outline, Package Outline
D
8
5
c
E1
1
E
4
α
A1
A
L
A2
L1
CP
b
e
TSSOP8AM
Note: Drawing is not to scale.
Table 26. TSSOP8 – 8 lead Thin Shrink Small Outline, Package Mechanical Data
mm
inches
Symbol
Typ.
Min.
A
0.050
0.150
0.800
1.050
b
0.190
c
0.090
A2
Typ.
Min.
1.200
A1
1.000
CP
Max.
0.0472
0.0020
0.0059
0.0315
0.0413
0.300
0.0075
0.0118
0.200
0.0035
0.0079
0.0394
0.100
0.0039
D
3.000
2.900
3.100
0.1181
0.1142
0.1220
e
0.650
–
–
0.0256
–
–
E
6.400
6.200
6.600
0.2520
0.2441
0.2598
E1
4.400
4.300
4.500
0.1732
0.1693
0.1772
L
0.600
0.450
0.750
0.0236
0.0177
0.0295
L1
1.000
0°
8°
α
36/39
Max.
0.0394
0°
8°
M95256, M95128
PART NUMBERING
Table 27. Ordering Information Scheme
Example:
M95256
–
W MN
6
T
P
Device Type
M95 = SPI serial access EEPROM
Device Function
256 = 256 Kbit (32768 x 8)
128 = 128 Kbit (16384 x 8)
Operating Voltage
blank = VCC = 4.5 to 5.5V
W = VCC = 2.5 to 5.5V
R = VCC = 1.8 to 5.5V
Package
BN = PDIP8
MN = SO8 (150 mil width)
MW = SO8 (200 mil width)
DW = TSSOP8 (169 mil width)
Device Grade
6 = Industrial temperature range, –40 to 85 °C.
Device tested with standard test flow
3 = Device tested with High Reliability Certified Flow1.
Automotive temperature range (–40 to 125 °C)
Option
blank = Standard Packing
T = Tape and Reel Packing
Plating Technology
blank = Standard SnPb plating
P = Lead-Free and RoHS compliant
G = Lead-Free, RoHS compliant, Sb2O3-free and TBBA-free
Note: 1. ST strongly recommends the use of the Automotive Grade devices for use in an automotive environment. The High Reliability Certified Flow (HRCF) is described in the quality note QNEE9801. Please ask your nearest ST sales office for a copy.
For a list of available options (speed, package,
etc.) or for further information on any aspect of this
device, please contact your nearest ST Sales Office.
37/39
M95256, M95128
REVISION HISTORY
Table 28. Document Revision History
Date
Rev.
17-Nov-1999
2.1
New -V voltage range added (including the tables for DC characteristics, AC characteristics,
and ordering information).
07-Feb-2000
2.2
New -V voltage range extended to M95256 (including AC characteristics, and ordering
information).
22-Feb-2000
2.3
tCLCH and tCHCL, for the M95xxx-V, changed from 1µs to 100ns
15-Mar-2000
2.4
-V voltage range changed to 2.7-3.6V
29-Jan-2001
2.5
Lead Soldering Temperature in the Absolute Maximum Ratings table amended
Illustrations and Package Mechanical data updated
12-Jun-2001
2.6
Correction to header of Table 12B
TSSOP14 Illustrations and Package Mechanical data updated
Document promoted from Preliminary Data to Full Data Sheet
08-Feb-2002
2.7
Announcement made of planned upgrade to 10 MHz clock for the 5V, –40 to 85°C, range.
09-Aug-2002
2.8
M95128 split off to its own datasheet. Data added for new and forthcoming products, including
availability of the SO8 narrow package.
24-Feb-2003
2.9
Omission of SO8 narrow package mechanical data remedied
26-Jun-2003
2.10
-V voltage range removed
21-Nov-2003
3.0
Table of contents, and Pb-free options added. -S voltage range extended to -R. VIL(min)
improved to –0.45V
17-Mar-2004
4.0
Absolute Maximum Ratings for VIO(min) and VCC(min) changed. Soldering temperature
information clarified for RoHS compliant devices. Device grade information clarified
21-Oct-2004
5.0
M95128 datasheet merged back in. Product List summary table added. AEC-Q100-002
compliance. Device Grade information clarified. tHHQX corrected to tHHQV. 10MHz product
becomes standard
38/39
Description of Revision
M95256, M95128
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted
by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject
to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not
authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
The ST logo is a registered trademark of STMicroelectronics.
All other names are the property of their respective owners
© 2004 STMicroelectronics - All rights reserved
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39/39