M95128-A125
M95128-A145
Automotive 128-Kbit serial SPI bus EEPROMs with high-speed clock
Features
■Compatible with the Serial Peripheral Interface (SPI) bus
■Memory array
–128 Kbits ( Kbytes) of EEPROM
–Page size: 64 bytes
–Write protection by block: 1/4, 1/2 or whole memory
–Additional Write lockable Page (Identification page)
■Extended temperature and voltage ranges
–Up to 125 °C: 1.8 V to 5.5 V
–Up to 145 °C: 2.5 V to 5.5 V
■High speed clock frequency
–20 MHz for VCC ≥ 4.5 V
–10 MHz for VCC ≥ 2.5 V
–5 MHz for VCC ≥ 1.8 V
■Schmitt trigger inputs for noise filtering
■Short Write cycle time
–Byte Write within 4 ms
–Page Write within 4 ms
■Write cycle endurance
–4 million Write cycles at 25 °C
–1.2 million Write cycles at 85 °C
–600 k Write cycles at 125 °C
–400 k Write cycles at 145 °C
■Data retention
–40 years at 55 °C
–100 years at 25 °C
■ESD Protection (Human Body Model)
–4000 V
■Packages
–RoHS-compliant and halogen-free (ECOPACK2®)
Datasheet − preliminary data
SO8 (MN) 150 mil width
TSSOP8 (DW) 169 mil width
UFDFPN8 (MC) 2 x 3 mm
April 2012 |
Doc ID 023103 Rev 1 |
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This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to |
www.st.com |
change without notice. |
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Contents |
M95128-A125 M95128-A145 |
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Contents
1 |
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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Signal description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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2.1 |
Serial Data output (Q) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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2.2 |
Serial Data input (D) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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2.3 |
Serial Clock (C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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Chip Select (S) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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2.5 |
Hold |
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2.6 |
Write Protect |
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2.7 |
VSS ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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2.8 |
VCC supply voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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Operating features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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3.1 Active power and Standby power modes . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.2 SPI modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.3 Hold mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.4 Protocol control and data protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
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3.4.1 |
Protocol control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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3.4.2 |
Status Register and data protection . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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3.5 |
Identification page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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Instructions |
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4.1 |
Write Enable (WREN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.2 |
Write Disable (WRDI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.3 |
Read Status Register (RDSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.4 |
Write Status Register (WRSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.5 |
Read from Memory Array (READ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.6 |
Write to Memory Array (WRITE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.7 |
Read Identification Page (RDID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.8 |
Write Identification Page (WRID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.9 |
Read Lock Status (RDLS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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4.10 |
Lock Identification Page (LID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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Contents |
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5 |
Application design recommendations . . . . . . . . . . . . . . . . . . . . . |
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5.1 Supply voltage (VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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5.1.1 Operating supply voltage VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.1.2 Power-up conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 5.1.3 Power-down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.2 Implementing devices on SPI bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5.3 Cycling with Error Correction Code (ECC) . . . . . . . . . . . . . . . . . . . . . . . . 26
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Delivery state . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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7 |
Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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DC and AC parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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9 |
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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10 |
Part numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
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11 |
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
38 |
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List of tables |
M95128-A125 M95128-A145 |
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List of tables
Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Table 2. Status Register format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Table 3. Write-protected block size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Table 4. Protection modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Table 5. Device identification bytes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Table 6. Instruction set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 7. Significant bits within the two address bytes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 8. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Table 9. Cycling performance by groups of 4 bytes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 10. Operating conditions (voltage range W, temperature range 4). . . . . . . . . . . . . . . . . . . . . . 28 Table 11. Operating conditions (voltage range R, temperature range 3) . . . . . . . . . . . . . . . . . . . . . . 28 Table 12. Operating conditions (voltage range R, temperature range 3)
for high speed communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 13. DC characteristics (voltage range W, temperature range 4). . . . . . . . . . . . . . . . . . . . . . . . 29 Table 14. DC characteristics (voltage range R, temperature range 3) . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 15. AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Table 16. SO8N – 8-lead plastic small outline, 150 mils body width, package mechanical data . . . . 34 Table 17. TSSOP8 – 8-lead thin shrink small outline, package mechanical data. . . . . . . . . . . . . . . . 35 Table 18. UFDFPN8 (MLP8) 8-lead ultra thin fine pitch dual flat package no lead
2 x 3 mm, data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 19. Ordering information scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Table 20. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
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List of figures |
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List of figures
Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Figure 2. 8-pin package connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 3. SPI modes supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Figure 4. Hold mode activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Figure 5. Write Enable (WREN) sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Figure 6. Write Disable (WRDI) sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Figure 7. Read Status Register (RDSR) sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 8. Write Status Register (WRSR) sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Figure 9. Read from Memory Array (READ) sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Figure 10. Byte Write (WRITE) sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Figure 11. Page Write (WRITE) sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Figure 12. Read Identification Page sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 13. Write Identification Page sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 14. Read Lock Status sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 15. Lock ID sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 16. Bus master and memory devices on the SPI bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Figure 17. AC measurement I/O waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Figure 18. Serial input timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Figure 19. Hold timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Figure 20. Serial output timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Figure 21. SO8N – 8-lead plastic small outline, 150 mils body width, package outline . . . . . . . . . . . . 34 Figure 22. TSSOP8 – 8-lead thin shrink small outline, package outline . . . . . . . . . . . . . . . . . . . . . . . 35 Figure 23. UFDFPN8 (MLP8) - 8-lead ultra thin fine pitch dual flat no lead, package
outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
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Description |
M95128-A125 M95128-A145 |
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The M95128-A125 and M95128-A145 are 128-Kbit serial EEPROM Automotive grade devices operating up to 145°C. They are compliant with the very high level of reliability defined by the Automotive standard AEC-Q100 grade 0.
The devices are accessed by a simple serial SPI compatible interface running up to 20 MHz.
The memory array is based on advanced true EEPROM technology (Electrically Erasable PROgrammable Memory). The M95128-A125 and M95128-A145 are byte-alterable memories (16384 × 8 bits) organized as 256 pages of 64 bytes in which the data integrity is significantly improved with an embedded Error Correction Code logic.
The M95128-A125 and M95128-A145 offer an additional Identification Page (64 bytes) in which the ST device identification can be read. This page can also be used to store sensitive application parameters which can be later permanently locked in read-only mode.
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(IGH VOLTAGE |
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#ONTROLTLOGIC |
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GENERATOR |
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ANDNCOUNTER |
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99DECODER |
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)DENTIFICATION PAGE |
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88DECODER |
3IZEEOF THE 2EAD ONLY %%02/- AREA
-3 6
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Description |
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Figure 2. 8-pin package connections |
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1. See Package mechanical data section for package dimensions and how to identify pin-1.
Table 1. |
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Signal names |
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Signal name |
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C |
Serial Clock |
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Serial data input |
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Serial data output |
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Chip Select |
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Write Protect |
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Hold |
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VCC |
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VSS |
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Signal description |
M95128-A125 M95128-A145 |
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All input signals must be held high or low (according to voltages of VIH or VIL, as specified in Table 13 and Table 14)). These signals are described below.
This output signal is used to transfer data serially out of the device during a Read operation. Data is shifted out on the falling edge of Serial Clock (C), most significant bit (MSB) first. In all other cases, the Serial Data output is in high impedance.
This input signal is used to transfer data serially into the device. D input receives instructions, addresses, and the data to be written. Values are latched on the rising edge of Serial Clock (C), most significant bit (MSB) first.
This input signal allows to synchronize 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).
Driving Chip Select (S) low selects the device in order to start communication. Driving Chip Select (S) high deselects the device and Serial Data output (Q) enters the high impedance state.
The Hold (HOLD) signal is used to pause any serial communications with the device without deselecting the device.
This pin is used to write-protect the Status Register.
2.7VSS ground
VSS is the reference for all signals, including the VCC supply voltage.
2.8VCC supply voltage
VCC is the supply voltage pin.
Refer to Section 3.1: Active power and Standby power modes and to Section 5.1: Supply voltage (VCC).
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Operating features |
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When Chip Select (S) is low, the device is selected and in the Active power mode.
When Chip Select (S) is high, the device is deselected. If a Write cycle is not currently in progress, the device then goes in to the Standby power mode, and the device consumption drops to ICC1, as specified in Table 13 and Table 14.
The device 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 3, 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)
CPOL CPHA |
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MSB |
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Q |
MSB |
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Operating features |
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The Hold (HOLD) signal is used to pause any serial communications with the device without resetting the clocking sequence.
The Hold mode starts when the Hold (HOLD) signal is driven low and the Serial Clock (C) is low (as shown in Figure 4). During the Hold mode, the Serial Data output (Q) is high impedance, and the signals present on Serial Data input (D) and Serial Clock (C) are not decoded. The Hold mode ends when the Hold (HOLD) signal is driven high and the Serial Clock (C) is or becomes low.
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Deselecting the device while it is in Hold mode resets the paused communication.
The Chip Select (S) input offers a built-in safety feature, as the S input is edge-sensitive as well as level-sensitive: after power-up, the device is not 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, in order to start the first operation.
For Write commands (WRITE, WRSR, WRID, LID) to be accepted and executed:
●the Write Enable Latch (WEL) bit must be set by a Write Enable (WREN) instruction
●a falling edge and a low state on Chip Select (S) during the whole command must be decoded
●instruction, address and input data must be sent as multiple of eight bits
●the command must include at least one data byte
●Chip Select (S) must be driven high exactly after a data byte boundary
Write command can be discarded at any time by a rising edge on Chip Select (S) outside of a byte boundary.
To execute Read commands (READ, RDSR, RDID, RDLS), the device must decode:
●a falling edge and a low level on Chip Select (S) during the whole command
●instruction and address as multiples of eight bits (bytes)
From this step, data bits are shifted out until the rising edge on Chip Select (S).
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Doc ID 023103 Rev 1 |
M95128-A125 M95128-A145 |
Operating features |
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The Status Register format is shown in Table 2 and the status and control bits of the Status Register are as follows:
Table 2. |
Status Register format |
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b7 |
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b6 |
b5 |
b4 |
b3 |
b2 |
b1 |
b0 |
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SRWD |
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0 |
0 |
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0 |
BP1 |
BP0 |
WEL |
WIP |
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Status Register Write Protect
Block Protect bits
Write Enable Latch bit
Write In Progress bit
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Bits b6, b5, b4 are always read as 0. |
WIP bit
The WIP bit (Write In Progress) is a read-only flag that indicates the Ready/Busy state of the device. When a Write command (WRITE, WRSR, WRID, LID) has been decoded and a Write cycle (tW) is in progress, the device is busy and the WIP bit is set to 1. When WIP=0, the device is ready to decode a new command.
During a Write cycle, reading continuously the WIP bit allows to detect when the device becomes ready (WIP=0) to decode a new command.
WEL bit
The WEL bit (Write Enable Latch) bit is a flag that indicates the status of the internal Write Enable Latch. When WEL is set to 1, the Write instructions (WRITE, WRSR, WRID, LID) are executed; when WEL is set to 0, any decoded Write instruction is not executed.
The WEL bit is set to 1 with the WREN instruction. The WEL bit is reset to 0 after the following events:
●Write Disable (WRDI) instruction completion
●Write instructions (WRITE, WRSR, WRID, LID) completion including the write cycle time tW
●Power-up
BP1, BP0 bits
The Block Protect bits (BP1, BP0) are non-volatile. BP1,BP0 bits define the size of the memory block to be protected against write instructions, as defined in Table 2. These bits are written with the Write Status Register (WRSR) instruction, provided that the Status Register is not protected (refer to SRWD bit and W input signal).
Doc ID 023103 Rev 1 |
11/39 |
Operating features |
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M95128-A125 M95128-A145 |
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Table 3. |
Write-protected block size |
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Status Register bits |
Protected block |
Protected array addresses |
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BP1 |
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BP0 |
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0 |
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None |
None |
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0 |
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1 |
Upper quarter |
3000h-3FFFh |
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1 |
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Upper half |
2000h-3FFFh |
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1 |
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Whole memory |
0000h - 3FFFh plus Identification page |
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SRWD bit and W input signal
The Status Register Write Disable (SRWD) bit is operated in conjunction with the Write Protect pin (W) signal. When the SRWD bit is written to 0, it is possible to write the Status Register, regardless of whether the pin Write Protect (W) is driven high or low.
When the SRWD bit is written to 1, two cases have to be considered, depending on the state of the W input pin:
●Case 1: if pin W is driven high, it is possible to write the Status Register.
●Case 2: if pin W is driven low, it is not possible to write the Status Register (WRSR is discarded) and therefore SRWD,BP1,BP0 bits cannot be changed (the size of the protected memory block defined by BP1,BP0 bits is frozen).
Case 2 can be entered in either sequence:
●Writing SRWD bit to 1 after driving pin W low, or
●Driving pin W low after writing SRWD bit to 1.
The only way to exit Case 2 is to pull pin W high.
Note: if pin W is permanently tied high, the Status Register cannot be write-protected.
The protection features of the device are summarized in Table 4.
Table 4. |
Protection modes |
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SRWD bit |
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signal |
Status |
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W |
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0 |
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X |
Status Register is writable. |
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1 |
1 |
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1 |
0 |
Status Register is write-protected. |
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12/39 |
Doc ID 023103 Rev 1 |