M25P40 4 Mbit, Low Voltage, Serial Flash Memory With 25 MHz SPI Bus Interface FEATURES SUMMARY ■ 4 Mbit of Flash Memory ■ Page Program (up to 256 Bytes) in 1.5ms (typical) ■ Sector Erase (512 Kbit) in 2 s (typical) ■ Bulk Erase (4 Mbit) in 5 s (typical) ■ 2.7 V to 3.6 V Single Supply Voltage ■ SPI Bus Compatible Serial Interface ■ 25 MHz Clock Rate (maximum) ■ Deep Power-down Mode 1 µA (typical) ■ Electronic Signature (12h) ■ More than 100,000 Erase/Program Cycles per Sector ■ More than 20 Year Data Retention Figure 1. Packages 8 1 SO8 (MN) 150 mil width VFQFPN8 (MP) (MLP8) June 2003 1/35 M25P40 SUMMARY DESCRIPTION The M25P40 is a 4 Mbit (512K x 8) 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 memory is organized as 8 sectors, each containing 256 pages. Each page is 256 bytes wide. Thus, the whole memory can be viewed as consisting of 2048 pages, or 524,288 bytes. The whole memory can be erased using the Bulk Erase instruction, or a sector at a time, using the Sector Erase instruction. Figure 3. SO and VFQFPN Connections M25P40 S Q W VSS 1 2 3 4 8 7 6 5 VCC HOLD C D AI04091B Figure 2. Logic Diagram VCC D Q Note: 1. See page 31 (onwards) for package dimensions, and how to identify pin-1. C S M25P40 W HOLD VSS AI04090 Table 1. Signal Names C Serial Clock D Serial Data Input Q Serial Data Output S Chip Select W Write Protect HOLD Hold VCC Supply Voltage VSS Ground 2/35 M25P40 SIGNAL DESCRIPTION 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 programmed. 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 (Q) is at high impedance. Unless an internal Program, Erase or Write Status Register cycle is in progress, the device will be in the Standby mode (this is not the Deep Power-down mode). Driving Chip Select (S) Low enables 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 program or erase instructions (as specified by the values in the BP2, BP1 and BP0 bits of the Status Register). 3/35 M25P40 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 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: 1. The Write Protect (W) and Hold (HOLD) signals should be driven, High or Low as appropriate. Figure 5. SPI Modes Supported CPOL CPHA 0 0 C 1 1 C D Q MSB MSB AI01438B 4/35 M25P40 OPERATING FEATURES 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 and Bulk 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 either a sector at a time, using the Sector Erase (SE) instruction, or throughout the entire memory, using the Bulk Erase (BE) instruction. This starts an internal Erase cycle (of duration tSE or tBE). The Erase instruction must be preceeded 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 or BE) can be achieved by not waiting for the worst case delay (tW, tPP, tSE, or tBE). 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 (S) is Low, the device is enabled, and in the Active Power mode. When Chip Select (S) 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 in to the Stand-by Power mode. The device consumption drops to I CC1. 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 Electronic Signature (RES) 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 inadvertant 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. 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. 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, BP2, BP1, BP0) become read-only bits. 5/35 M25P40 Protection Modes The environments where non-volatile memory devices are used can be very noisy. No SPI device can operate correctly in the presence of excessive noise. To help combat this, the M25P40 boasts the following data protection mechanisms: ■ Power-On Reset and an internal timer (tPUW) can provide protection against inadvertant changes while the power supply is outside the operating specification. ■ 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. ■ 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: – Write Status Register (WRSR) instruction completion – Page Program (PP) instruction completion – Sector Erase (SE) instruction completion – Bulk Erase (BE) instruction completion ■ The Block Protect (BP2, BP1, BP0) bits allow part of the memory to be configured as readonly. This is the Software Protected Mode (SPM). ■ The Write Protect (W) signal allows the Block Protect (BP2, BP1, BP0) bits and Status Register Write Disable (SRWD) bit to be protected. This is the Hardware Protected Mode (HPM). ■ In addition to the low power consumption feature, the Deep Power-down mode offers extra software protection from inadvertant Write, Program and Erase instructions, as all instructions are ignored except one particular instruction (the Release from Deep Powerdown instruction). – Power-up – Write Disable (WRDI) instruction completion Table 2. Protected Area Sizes Status Register Content Memory Content BP2 Bit BP1 Bit BP0 Bit 0 0 0 none All sectors1 (eight sectors: 0 to 7) 0 0 1 Upper eighth (Sector 7) Lower seven-eighths (seven sectors: 0 to 6) 0 1 0 Upper quarter (two sectors: 6 and 7) Lower three-quarters (six sectors: 0 to 5) 0 1 1 Upper half (four sectors: 4 to 7) Lower half (four sectors: 0 to 3) 1 0 0 All sectors (eight sectors: 0 to 7) none 1 0 1 All sectors (eight sectors: 0 to 7) none 1 1 0 All sectors (eight sectors: 0 to 7) none 1 1 1 All sectors (eight sectors: 0 to 7) none Protected Area Unprotected Area Note: 1. The device is ready to accept a Bulk Erase instruction if, and only if, all Block Protect (BP2, BP1, BP0) are 0. 6/35 M25P40 Hold Condition 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 (S) Low. The Hold condition starts on the falling edge of the Hold (HOLD) signal, provided that this coincides with Serial Clock (C) being Low (as shown in Figure 6). The Hold condition ends on the rising edge of the Hold (HOLD) signal, provided that this coincides with Serial Clock (C) being Low. If the falling edge does not coincide with Serial Clock (C) being Low, the Hold condition starts after Serial Clock (C) next goes Low. Similarly, if the rising edge does not coincide with Serial Clock (C) being Low, the Hold condition ends after Serial Clock (C) next goes Low. (This is shown in Figure 6). 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. Normally, the device is kept selected, with Chip Select (S) 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 (S) 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 (S) Low. This prevents the device from going back to the Hold condition. Figure 6. Hold Condition Activation C HOLD Hold Condition (standard use) Hold Condition (non-standard use) AI02029D 7/35 M25P40 MEMORY ORGANIZATION The memory is organized as: ■ 524,288 bytes (8 bits each) ■ 8 sectors (512 Kbits, 65536 bytes each) ■ 2048 pages (256 bytes each). Each page can be individually programmed (bits are programmed from 1 to 0). The device is Sector or Bulk Erasable (bits are erased from 0 to 1) but not Page Erasable. Table 3. Memory Organization Sector 8/35 Address Range 7 70000h 7FFFFh 6 60000h 6FFFFh 5 50000h 5FFFFh 4 40000h 4FFFFh 3 30000h 3FFFFh 2 20000h 2FFFFh 1 10000h 1FFFFh 0 00000h 0FFFFh M25P40 Figure 7. Block Diagram HOLD W High Voltage Generator Control Logic S C D I/O Shift Register Q Address Register and Counter Status Register 256 Byte Data Buffer 7FFFFh Y Decoder Size of the read-only memory area 00000h 000FFh 256 Bytes (Page Size) X Decoder AI04986 9/35 M25P40 INSTRUCTIONS All instructions, addresses and data are shifted in and out of the device, most significant bit first. Serial Data Input (D) is sampled on the first rising edge of Serial Clock (C) after Chip Select (S) is driven Low. Then, the one-byte instruction code must be shifted in to the device, most significant bit first, on Serial Data Input (D), each bit being latched on the rising edges of Serial Clock (C). 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 (S) 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 Electronic Signature (RES) instruction, the shifted-in instruction sequence is followed by a data-out sequence. Chip Select (S) 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), Bulk Erase (BE), Write Status Register (WRSR), Write Enable (WREN), Write Disable (WRDI) or Deep Power-down (DP) instruction, Chip Select (S) must be driven High exactly at a byte boundary, otherwise the instruction is rejected, and is not executed. That is, Chip Select (S) must driven High when the number of clock pulses after Chip Select (S) being driven Low is an exact multiple of eight. 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 Description One-byte Instruction Code Address Bytes Dummy Bytes Data Bytes WREN Write Enable 0000 0110 0 0 0 WRDI Write Disable 0000 0100 0 0 0 RDSR Read Status Register 0000 0101 0 0 1 to ∞ WRSR Write Status Register 0000 0001 0 0 1 READ Read Data Bytes 0000 0011 3 0 1 to ∞ 0000 1011 3 1 1 to ∞ FAST_READ Read Data Bytes at Higher Speed PP Page Program 0000 0010 3 0 1 to 256 SE Sector Erase 1101 1000 3 0 0 BE Bulk Erase 1100 0111 0 0 0 DP Deep Power-down 1011 1001 0 0 0 Release from Deep Power-down, and Read Electronic Signature 0 3 1010 1011 1 to ∞ 0 0 0 RES Release from Deep Power-down 10/35 M25P40 Figure 8. Write Enable (WREN) Instruction Sequence S 0 1 2 3 4 5 6 7 C Instruction D High Impedance Q AI02281E (SE), Bulk Erase (BE) and Write Status Register (WRSR) instruction. The Write Enable (WREN) instruction is entered by driving Chip Select (S) Low, sending the instruction code, and then driving Chip Select (S) High. Write Enable (WREN) The Write Enable (WREN) instruction (Figure 8) sets the Write Enable Latch (WEL) bit. The Write Enable Latch (WEL) bit must be set prior to every Page Program (PP), Sector Erase Figure 9. Write Disable (WRDI) Instruction Sequence S 0 1 2 3 4 5 6 7 C Instruction D High Impedance Q AI03750D Write Disable (WRDI) The Write Disable (WRDI) instruction (Figure 9) resets the Write Enable Latch (WEL) bit. The Write Disable (WRDI) instruction is entered by driving Chip Select (S) Low, sending the instruction code, and then driving Chip Select (S) High. The Write Enable Latch (WEL) bit is reset under the following conditions: – Power-up – Write Disable (WRDI) instruction completion – Write Status Register (WRSR) instruction completion – Page Program (PP) instruction completion – Sector Erase (SE) instruction completion – Bulk Erase (BE) instruction completion 11/35 M25P40 Figure 10. Read Status Register (RDSR) Instruction Sequence and Data-Out 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 6 5 MSB 4 3 2 1 0 7 6 5 4 3 2 1 0 7 MSB AI02031E 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 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 10. Table 5. Status Register Format b7 SRWD b0 0 0 BP2 BP1 BP0 WEL WIP Status Register Write Protect Block Protect Bits Write Enable Latch Bit Write In Progress 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. 12/35 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 2) becomes protected against Page Program (PP) and Sector Erase (SE) instructions. The Block Protect (BP2, BP1, BP0) bits can be written provided that the Hardware Protected mode has not been set. The Bulk Erase (BE) instruction is executed if, and only if, both Block Protect (BP2, BP1, BP0) bits are 0. 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, BP2, BP1, BP0) become read-only bits and the Write Status Register (WRSR) instruction is no longer accepted for execution. M25P40 Figure 11. Write Status Register (WRSR) Instruction 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 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, b1 and b0 of the Status Register. b6 and b5 are always read as 0. Chip Select (S) 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 (S) 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 2. 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. 13/35 M25P40 Table 6. Protection Modes W Signal SRWD Bit 1 0 0 0 1 1 0 1 Mode Write Protection of the Status Register Memory Content Protected Area1 Unprotected Area1 Software Protected (SPM) Status Register is Writable (if the WREN instruction has set the WEL bit) The values in the SRWD, BP2, BP1 and BP0 bits can be changed Protected against Page Program, Sector Erase and Bulk Erase Ready to accept Page Program and Sector Erase instructions Hardware Protected (HPM) Status Register is Hardware write protected The values in the SRWD, BP2, BP1 and BP0 bits cannot be changed Protected against Page Program, Sector Erase and Bulk Erase Ready to accept Page Program and Sector Erase instructions Note: 1. As defined by the values in the Block Protect (BP2, BP1, BP0) bits of the Status Register, as shown in Table 2. The protection features of the device are summarized in Table 6. 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. 14/35 (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 (BP2, 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 (BP2, BP1, BP0) bits of the Status Register, can be used. M25P40 Figure 12. Read Data Bytes (READ) Instruction Sequence and Data-Out Sequence S 0 1 2 3 4 5 6 7 8 9 10 28 29 30 31 32 33 34 35 36 37 38 39 C Instruction 24-Bit Address 23 22 21 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 AI03748D Note: 1. Address bits A23 to A19 are Don’t Care. Read Data Bytes (READ) The device is first selected by driving Chip Select (S) 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 (C). Then the memory contents, at that address, is shifted out on Serial Data Output (Q), each bit being shifted out, at a maximum frequency fR, during the falling edge of Serial Clock (C). The instruction sequence is shown in Figure 12. 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 (S) High. Chip Select (S) 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. 15/35 M25P40 Figure 13. Read Data Bytes at Higher Speed (FAST_READ) Instruction Sequence and Data-Out Sequence S 0 1 2 3 4 5 6 7 8 9 10 28 29 30 31 C Instruction 24 BIT ADDRESS 23 22 21 D 3 2 1 0 High Impedance Q S 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 C Dummy Byte D 7 6 5 4 3 2 1 0 DATA OUT 2 DATA OUT 1 Q 7 6 5 MSB 4 3 2 1 0 7 MSB 6 5 4 3 2 1 0 7 MSB AI04006 Note: 1. Address bits A23 to A19 are Don’t Care. Read Data Bytes at Higher Speed (FAST_READ) The device is first selected by driving Chip Select (S) 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 (C). Then the memory contents, at that address, is shifted out on Serial Data Output (Q), each bit being shifted out, at a maximum frequency fC, during the falling edge of Serial Clock (C). The instruction sequence is shown in Figure 13. The first byte addressed can be at any location. The address is automatically incremented to the 16/35 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 (S) High. Chip Select (S) 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. M25P40 Figure 14. Page Program (PP) Instruction Sequence S 0 1 2 3 4 5 6 7 8 9 10 28 29 30 31 32 33 34 35 36 37 38 39 C Instruction 24-Bit Address 23 22 21 D 3 2 Data Byte 1 1 0 7 6 5 4 3 2 0 1 MSB MSB 2078 2079 2077 2076 2075 2074 2073 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 2072 S 1 0 C Data Byte 2 D 7 6 5 4 3 2 Data Byte 3 1 MSB 0 7 6 5 MSB 4 3 2 Data Byte 256 1 0 7 6 5 4 3 2 MSB AI04082B Note: 1. Address bits A23 to A19 are Don’t Care. Page Program (PP) The Page Program (PP) instruction allows bytes to be programmed in the memory (changing bits from 1 to 0). 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 (S) Low, followed by the instruction code, three address bytes and at least one data byte on Serial Data Input (D). 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 (S) must be driven Low for the entire duration of the sequence. The instruction sequence is shown in Figure 14. 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 (S) 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 (S) is driven High, the selftimed 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 selftimed 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 Tables 3 and 2) is not executed. 17/35 M25P40 Figure 15. Sector Erase (SE) Instruction Sequence S 0 1 2 3 4 5 6 7 8 9 29 30 31 C Instruction 24 Bit Address 23 22 D 2 1 0 MSB AI03751D Note: 1. Address bits A23 to A19 are Don’t Care. Sector Erase (SE) 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 (S) Low, followed by the instruction code, and three address bytes on Serial Data Input (D). Any address inside the Sector (see Table 3) is a valid address for the Sector Erase (SE) instruction. Chip Select (S) must be driven Low for the entire duration of the sequence. The instruction sequence is shown in Figure 15. 18/35 Chip Select (S) 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 (S) 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 page which is protected by the Block Protect (BP2, BP1, BP0) bits (see Tables 3 and 2) is not executed. M25P40 Figure 16. Bulk Erase (BE) Instruction Sequence S 0 1 2 3 4 5 6 7 C Instruction D AI03752D Bulk Erase (BE) The Bulk Erase (BE) 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 Bulk Erase (BE) instruction is entered by driving Chip Select (S) Low, followed by the instruction code on Serial Data Input (D). Chip Select (S) must be driven Low for the entire duration of the sequence. The instruction sequence is shown in Figure 16. Chip Select (S) must be driven High after the eighth bit of the instruction code has been latched in, otherwise the Bulk Erase instruction is not executed. As soon as Chip Select (S) is driven High, the self-timed Bulk Erase cycle (whose duration is tBE) is initiated. While the Bulk 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 selftimed Bulk 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 Bulk Erase (BE) instruction is executed only if all Block Protect (BP2, BP1, BP0) bits are 0. The Bulk Erase (BE) instruction is ignored if one, or more, sectors are protected. 19/35 M25P40 Figure 17. Deep Power-down (DP) Instruction Sequence S 0 1 2 3 4 5 6 7 tDP C Instruction D Stand-by Mode Deep Power-down (DP) 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 (S) 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 I CC1 to I CC2, as specified in Table 12). Once the device has entered the Deep Powerdown mode, all instructions are ignored except the Release from Deep Power-down and Read Electronic Signature (RES) instruction. This releases the device from this mode. The Release from Deep Power-down and Read Electronic Signature (RES) instruction also allows the Electronic Signa- 20/35 Deep Power-down Mode AI03753D ture of the device to be output on Serial Data Output (Q). 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 (S) Low, followed by the instruction code on Serial Data Input (D). Chip Select (S) must be driven Low for the entire duration of the sequence. The instruction sequence is shown in Figure 17. Chip Select (S) 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 (S) 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. M25P40 Figure 18. Release from Deep Power-down and Read Electronic Signature (RES) Instruction Sequence and Data-Out Sequence S 0 1 2 3 4 5 6 7 8 9 10 28 29 30 31 32 33 34 35 36 37 38 C Instruction 23 22 21 D tRES2 3 Dummy Bytes 3 2 1 0 MSB Electronic Signature Out High Impedance Q 7 6 5 4 3 2 1 0 MSB Deep Power-down Mode Stand-by Mode AI04047C Release from Deep Power-down and Read Electronic Signature (RES) Once the device has entered the Deep Powerdown mode, all instructions are ignored except the Release from Deep Power-down and Read Electronic Signature (RES) instruction. Executing this instruction takes the device out of the Deep Power-down mode. The instruction can also be used to read, on Serial Data Output (Q), the 8-bit Electronic Signature of the device. Except while an Erase, Program or Write Status Register cycle is in progress, the Release from Deep Power-down and Read Electronic Signature (RES) instruction always provides access to the Electronic Signature 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 Electronic Signature (RES) 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. This instruction serves a second purpose. The device features an 8-bit Electronic Signature, whose value for the M25P40 is 12h. This can be read using the Release from Deep Power-down and Read Electronic Signature (RES) instruction. The device is first selected by driving Chip Select (S) Low. The instruction code is followed by 3 dummy bytes, each bit being latched-in on Serial Data Input (D) during the rising edge of Serial Clock (C). Then, the 8-bit Electronic Signature, stored in the memory, is shifted out on Serial Data Output (Q), each bit being shifted out during the falling edge of Serial Clock (C). The instruction sequence is shown in Figure 18. The Release from Deep Power-down and Read Electronic Signature (RES) instruction is terminated by driving Chip Select (S) High after the Electronic Signature has been read at least once. Sending additional clock cycles on Serial Clock (C), while Chip Select (S) is driven Low, cause the Electronic Signature to be output repeatedly. When Chip Select (S) 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 (S) must remain High for at least tRES2(max), as specified in Table 13. Once in the Stand-by Power mode, the device waits to be selected, so that it can receive, decode and execute instructions. 21/35 M25P40 Figure 19. Release from Deep Power-down (RES) Instruction Sequence S 0 1 2 3 4 5 6 7 tRES1 C Instruction D High Impedance Q Deep Power-down Mode Stand-by Mode AI04078B Driving Chip Select (S) High after the 8-bit instruction byte has been received by the device, but before the whole of the 8-bit Electronic Signature has been transmitted for the first time (as shown in Figure 19), still insures that the device is put into 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 22/35 the device was previously in the Deep Powerdown mode, though, the transition to the Stand-by Power mode is delayed by t RES1, and Chip Select (S) must remain High for at least tRES1(max), as specified in Table 13. Once in the Stand-by Power mode, the device waits to be selected, so that it can receive, decode and execute instructions. M25P40 POWER-UP AND POWER-DOWN At Power-up and Power-down, the device must not be selected (that is Chip Select (S) must follow the voltage applied on VCC) until V CC reaches the correct value: – VCC(min) at Power-up, and then for a further delay of tVSL – VSS at Power-down Usually a simple pull-up resistor on Chip Select (S) can be used to insure safe and proper Power-up and Power-down. To avoid data corruption and inadvertent write operations during power up, a Power On Reset (POR) circuit is included. The logic inside the device is held reset while V CC is less than the POR threshold value, V WI – all operations are disabled, and the device does not respond to any instruction. Moreover, the device ignores all Write Enable (WREN), Page Program (PP), Sector Erase (SE), Bulk Erase (BE) and Write Status Register (WRSR) instructions until a time delay of tPUW has elapsed after the moment that V CC rises above the VWI threshold. However, the correct operation of the device is not guaranteed if, by this time, VCC is still below VCC(min). No Write Status Register, Program or Erase instructions should be sent until the later of: – tPUW after VCC passed the V WI threshold – tVSL afterVCC passed the VCC(min) level These values are specified in Table 7. If the delay, tVSL, has elapsed, after VCC has risen above VCC(min), the device can be selected for READ instructions even if the tPUW delay is not yet fully elapsed. At Power-up, the device is in the following state: – The device is in the Standby mode (not the Deep Power-down mode). – The Write Enable Latch (WEL) bit is reset. Normal precautions must be taken for supply rail decoupling, to stablise the VCC feed. Each device in a system should have the VCC rail decoupled by a suitable capacitor close to the package pins. (Generally, this capacitor is of the order of 0.1µF). At Power-down, when VCC drops from the operating voltage, to below the POR threshold value, VWI, all operations are disabled and the device does not respond to any instruction. (The designer needs to be aware that if a Power-down occurs while a Write, Program or Erase cycle is in progress, some data corruption can result.) Figure 20. Power-up Timing VCC VCC(max) Program, Erase and Write Commands are Rejected by the Device Chip Selection Not Allowed VCC(min) Reset State of the Device tVSL Read Access allowed Device fully accessible VWI tPUW time AI04009C 23/35 M25P40 Table 7. Power-Up Timing and VWI Threshold Symbol 1 Parameter Min. Max. Unit VCC(min) to S low 10 tPUW1 Time delay to Write instruction 1 10 ms VWI1 Write Inhibit Voltage 1 2 V tVSL µs Note: 1. These 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 24/35 FFh). The Status Register contains 00h (all Status Register bits are 0). M25P40 MAXIMUM RATING Stressing the device above the rating listed in the Absolute Maximum Ratings" table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those indicated in the Operating sections of this specification is not im- plied. 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 8. Absolute Maximum Ratings Symbol Parameter TSTG Storage Temperature TLEAD Lead Temperature during Soldering (20 seconds max.)1 Min. Max. Unit –65 150 °C SO 235 °C VFQFPN 235 °C VIO Input and Output Voltage (with respect to Ground) –0.6 4.0 V VCC Supply Voltage –0.6 4.0 V VESD Electrostatic Discharge Voltage (Human Body model) 2 –2000 2000 V Note: 1. IPC/JEDEC J-STD-020A 2. JEDEC Std JESD22-A114A (C1=100 pF, R1=1500 Ω, R2=500 Ω) 25/35 M25P40 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 9. Operating Conditions Symbol VCC TA Parameter Min. Max. Unit Supply Voltage 2.7 3.6 V Ambient Operating Temperature –40 85 °C Min. Max. Unit Table 10. AC Measurement Conditions Symbol CL Parameter Load Capacitance 30 Input Rise and Fall Times pF 5 ns Input Pulse Voltages 0.2VCC to 0.8VCC V Input and Output Timing Reference Voltages 0.3VCC to 0.7VCC V Note: 1. Output Hi-Z is defined as the point where data out is no longer driven. Figure 21. AC Measurement I/O Waveform Input Levels Input and Output Timing Reference Levels 0.8VCC 0.7VCC 0.3VCC 0.2VCC AI00825B Table 11. Capacitance Symbol COUT CIN Parameter Output Capacitance (Q) Input Capacitance (other pins) Test Condition Max. Unit VOUT = 0V 8 pF VIN = 0V 6 pF Note: Sampled only, not 100% tested, at TA=25°C and a frequency of 20 MHz. 26/35 Min. M25P40 Table 12. DC Characteristics Symbol Test Condition (in addition to those in Table 9) Parameter Min. Max. Unit ILI Input Leakage Current ±2 µA ILO Output Leakage Current ±2 µA ICC1 Standby Current S = VCC, VIN = VSS or VCC 50 µA ICC2 Deep Power-down Current S = VCC, VIN = VSS or VCC 10 µA ICC3 Operating Current (READ) C = 0.1VCC / 0.9.VCC at 25 MHz, Q = open 4 mA ICC4 Operating Current (PP) S = VCC 15 mA ICC5 Operating Current (WRSR) S = VCC 15 mA ICC6 Operating Current (SE) S = VCC 15 mA ICC7 Operating Current (BE) S = VCC 15 mA VIL Input Low Voltage – 0.5 0.3VCC 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 13. AC Characteristics Test conditions specified in Table 9 and Table 10 Symbol Alt. fC fC fR Parameter Min. Typ. Max. Unit Clock Frequency for the following instructions: FAST_READ, PP, SE, BE, DP, RES, WREN, WRDI, RDSR, WRSR D.C. 25 MHz Clock Frequency for READ instructions D.C. 20 MHz tCH 1 tCLH Clock High Time 18 ns tCL 1 tCLL Clock Low Time 18 ns tCLCH 2 Clock Rise Time3 (peak to peak) 0.1 V/ns tCHCL 2 Clock Fall Time3 (peak to peak) 0.1 V/ns S Active Setup Time (relative to C) 10 ns S Not Active Hold Time (relative to C) 10 ns tSLCH tCSS tCHSL tDVCH tDSU Data In Setup Time 5 ns tCHDX tDH Data In Hold Time 5 ns tCHSH S Active Hold Time (relative to C) 10 ns tSHCH S Not Active Setup Time (relative to C) 10 ns 100 ns tSHSL tCSH S Deselect Time tSHQZ 2 tDIS Output Disable Time 15 ns tCLQV tV Clock Low to Output Valid 15 ns 27/35 M25P40 Test conditions specified in Table 9 and Table 10 Symbol Alt. tCLQX tHO Parameter Output Hold Time Min. Typ. Max. Unit 0 ns tHLCH HOLD Setup Time (relative to C) 10 ns tCHHH HOLD Hold Time (relative to C) 10 ns tHHCH HOLD Setup Time (relative to C) 10 ns tCHHL HOLD Hold Time (relative to C) 10 ns 2 tLZ HOLD to Output Low-Z 15 ns tHLQZ 2 tHZ HOLD to Output High-Z 20 ns tHHQX tWHSL 4 Write Protect Setup Time 20 ns tSHWL 4 Write Protect Hold Time 100 ns S High to Deep Power-down Mode 3 µs tRES1 2 S High to Standby Mode without Electronic Signature Read 3 µs tRES2 2 S High to Standby Mode with Electronic Signature Read 1.8 µs 5 15 ms 1.5 5 ms tDP 2 tW Write Status Register Cycle Time tPP Page Program Cycle Time tSE Sector Erase Cycle Time 2 3 s tBE Bulk Erase Cycle Time 5 10 s Note: 1. 2. 3. 4. 28/35 tCH + tCL must be greater than or equal to 1/ fC Value guaranteed by characterization, not 100% tested in production. Expressed as a slew-rate. Only applicable as a constraint for a WRSR instruction when SRWD is set at 1. M25P40 Figure 22. Serial Input Timing tSHSL S tCHSL tSLCH tCHSH tSHCH C tDVCH tCHCL tCHDX D Q MSB IN tCLCH LSB IN High Impedance AI01447C Figure 23. Write Protect Setup and Hold Timing during WRSR when SRWD=1 W tSHWL tWHSL S C D High Impedance Q AI07439 29/35 M25P40 Figure 24. Hold Timing S tHLCH tCHHL tHHCH C tCHHH tHLQZ tHHQX Q D HOLD AI02032 Figure 25. Output Timing S tCH C tCLQV tCLQX tCLQV tCL tSHQZ tCLQX LSB OUT Q tQLQH tQHQL D ADDR.LSB IN AI01449D 30/35 M25P40 PACKAGE MECHANICAL 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. 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 1.27 Typ. 0.050 8 0.10 0.004 31/35 M25P40 VFQFPN8 – 8-contact Very-thin Fine-pitch QFP No-lead, Package Outline D D1 E E1 E2 e b θ A D2 A2 L A1 A3 VFQFPN-01 Note: Drawing is not to scale. VFQFPN8 – 8-contact Very-thin Fine-pitch QFP No-lead, Package Mechanical Data mm inches Symb. Typ. A 0.85 A1 0.00 Max. Typ. 1.00 0.0335 0.05 A2 0.65 0.0256 A3 0.20 0.0079 b 0.40 D 6.00 0.2362 D1 5.75 0.2264 D2 3.40 E 5.00 0.1969 E1 4.75 0.1870 E2 4.00 e 1.27 L 0.60 θ 32/35 Min. 0.35 3.20 3.80 0.48 3.60 4.20 0.0157 0.1339 0.1575 Min. Max. 0.0394 0.0000 0.0020 0.0138 0.0189 0.1260 0.1417 0.1496 0.1654 0.0197 0.0295 0.0500 0.50 0.75 12° 0.0236 12° M25P40 PART NUMBERING Table 14. Ordering Information Scheme Example: M25P40 – V MN 6 T Device Type M25P Device Function 40 = 4 Mbit (512K x 8) Operating Voltage V = VCC = 2.7 to 3.6V Package MN = SO8 (150 mil width) MP = VFQFPN8 (MLP8) Temperature Range 6 = –40 to 85 °C Option T = Tape & Reel Packing 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. 33/35 M25P40 REVISION HISTORY Table 15. Document Revision History Date Rev. 12-Apr-2001 1.0 Document written 25-May-2001 1.1 Serial Paged Flash Memory renamed as Serial Flash Memory 11-Sep-2001 1.2 Changes to text: Signal Description/Chip Select; Hold Condition/1st para; Protection modes; Release from Power-down and Read Electronic Signature (RES); Power-up Repositioning of several tables and illustrations without changing their contents Power-up timing illustration; SO8W package removed Changes to tables: Abs Max Ratings/VIO; DC Characteristics/VIL 16-Jan-2002 1.3 FAST_READ instruction added. Document revised with new timings, VWI, ICC3 and clock slew rate. Descriptions of Polling, Hold Condition, Page Programming, Release for Deep Powerdown made more precise. Value of tW(max) modified. 12-Sep-2002 1.4 Clarification of descriptions of entering Stand-by Power mode from Deep Power-down mode, and of terminating an instruction sequence or data-out sequence. VFQFPN8 package (MLP8) added. Document promoted to Preliminary Data. 13-Dec-2002 1.5 Typical Page Program time improved. Deep Power-down current changed. Write Protect setup and hold times specified, for applications that switch Write Protect to exit the Hardware Protection mode immediately before a WRSR, and to enter the Hardware Protection mode again immediately after. 12-Jun-2003 1.6 Document promoted from Preliminary Data to full Datasheet 34/35 Description of Revision M25P40 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 registered trademark of STMicroelectronics All other names are the property of their respective owners © 2003 STMicroelectronics - All Rights Reserved STMicroelectronics group of companies Australia - Brazil - Canada - China - Finland - France - Germany - Hong Kong India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States. www.st.com 35/35