MX25L1635EM2I-10G

MX25L1635E MX25L1635E DATASHEET P/N: PM1553 1 REV. 1.6, DEC. 12, 2012 MX25L1635E Content FEATURES................................................................................................................................................................... 5 General............................................................................................................................................................... 5 Performance........................................................................................................................................................ 5 Software Features............................................................................................................................................... 5 Hardware Features............................................................................................................................................. 6 GENERAL DESCRIPTION.......................................................................................................................................... 7 Table 1. Additional Feature Comparison............................................................................................................. 7 PIN CONFIGURATIONS .............................................................................................................................................. 8 PIN DESCRIPTION....................................................................................................................................................... 8 BLOCK DIAGRAM........................................................................................................................................................ 9 DATA PROTECTION................................................................................................................................................... 10 Table 2. Protected Area Sizes........................................................................................................................... 11 Table 3. 4K-bit Secured OTP Definition............................................................................................................. 11 Memory Organization................................................................................................................................................ 12 Table 4. Memory Organization (16Mb)............................................................................................................. 12 DEVICE OPERATION................................................................................................................................................. 13 Figure 1. Serial Modes Supported.................................................................................................................... 13 COMMAND DESCRIPTION........................................................................................................................................ 14 Table 5. Command Set...................................................................................................................................... 14 (1) Write Enable (WREN).................................................................................................................................. 15 (2) Write Disable (WRDI)................................................................................................................................... 15 (3) Read Identification (RDID)........................................................................................................................... 15 (4) Read Status Register (RDSR)..................................................................................................................... 16 (5) Write Status Register (WRSR)..................................................................................................................... 17 Table 6. Protection Modes................................................................................................................................. 17 (6) Read Data Bytes (READ)............................................................................................................................ 18 (7) Read Data Bytes at Higher Speed (FAST_READ)...................................................................................... 18 (8) 2 x I/O Read Mode (2READ)....................................................................................................................... 18 (9) 4 x I/O Read Mode (4READ)....................................................................................................................... 19 (10) Sector Erase (SE)...................................................................................................................................... 19 (11) Block Erase (BE)........................................................................................................................................ 20 (12) Chip Erase (CE)......................................................................................................................................... 20 (13) Page Program (PP)................................................................................................................................... 20 (14) 4 x I/O Page Program (4PP)...................................................................................................................... 21 (15) Deep Power-down (DP)............................................................................................................................. 21 (16) Release from Deep Power-down (RDP), Read Electronic Signature (RES)............................................. 21 (17) Read Electronic Manufacturer ID & Device ID (REMS), (REMS2), (REMS4)........................................... 22 P/N: PM1553 2 REV. 1.6, DEC. 12, 2012 MX25L1635E Table 7. ID Definitions ...................................................................................................................................... 22 (18) Enter Secured OTP (ENSO)...................................................................................................................... 23 (19) Exit Secured OTP (EXSO)......................................................................................................................... 23 (20) Read Security Register (RDSCUR)........................................................................................................... 23 (21) Write Security Register (WRSCUR)........................................................................................................... 24 Table 8. Security Register Definition................................................................................................................. 24 POWER-ON STATE.................................................................................................................................................... 25 ELECTRICAL SPECIFICATIONS............................................................................................................................... 26 Absolute Maximum Ratings ............................................................................................................................. 26 Figure 2. Maximum Negative Overshoot Waveform......................................................................................... 26 Capacitance...................................................................................................................................................... 26 Figure 3. Maximum Positive Overshoot Waveform........................................................................................... 26 Figure 4. Input Test Waveforms and Measurement Level................................................................................. 27 Figure 5. Output Loading.................................................................................................................................. 27 Table 9. DC Characteristics............................................................................................................................... 28 Table 10. AC Characteristics............................................................................................................................. 29 Timing Analysis......................................................................................................................................................... 30 Figure 6. Serial Input Timing............................................................................................................................. 30 Figure 7. Output Timing..................................................................................................................................... 30 Figure 8. WP# Setup Timing and Hold Timing during WRSR when SRWD=1.................................................. 31 Figure 9. Write Enable (WREN) Sequence (Command 06).............................................................................. 31 Figure 10. Write Disable (WRDI) Sequence (Command 04)............................................................................. 31 Figure 11. Read Identification (RDID) Sequence (Command 9F)..................................................................... 32 Figure 12. Read Status Register (RDSR) Sequence (Command 05)............................................................... 32 Figure 13. Write Status Register (WRSR) Sequence (Command 01).............................................................. 32 Figure 14. Read Data Bytes (READ) Sequence (Command 03)..................................................................... 33 Figure 15. Read at Higher Speed (FAST_READ) Sequence (Command 0B)................................................. 33 Figure 16. 2 x I/O Read Mode Sequence (Command BB)................................................................................ 34 Figure 17. 4 x I/O Read Mode Sequence (Command EB)................................................................................ 34 Figure 18. 4 x I/O Read enhance performance Mode Sequence (Command EB)............................................ 35 Figure 19. Page Program (PP) Sequence (Command 02).............................................................................. 36 Figure 20. 4 x I/O Page Program (4PP) Sequence (Command 38)................................................................. 36 Figure 21. Sector Erase (SE) Sequence (Command 20)................................................................................. 37 Figure 22. Block Erase (BE) Sequence (Command D8).................................................................................. 37 Figure 23. Chip Erase (CE) Sequence (Command 60 or C7).......................................................................... 37 Figure 24. Deep Power-down (DP) Sequence (Command B9)....................................................................... 38 Figure 25. Read Electronic Signature (RES) Sequence (Command AB)......................................................... 38 Figure 26. Release from Deep Power-down (RDP) Sequence (Command AB).............................................. 38 Figure 27. Read Electronic Manufacturer & Device ID (REMS) Sequence (Command 90 or EF or DF)......... 39 Figure 28. Power-up Timing.............................................................................................................................. 40 Table 11. Power-Up Timing .............................................................................................................................. 40 P/N: PM1553 3 REV. 1.6, DEC. 12, 2012 MX25L1635E Initial Delivery State.......................................................................................................................................... 40 OPERATING CONDITIONS........................................................................................................................................ 41 Figure 29. AC Timing at Device Power-Up........................................................................................................ 41 Figure 30. Power-Down Sequence................................................................................................................... 42 ERASE AND PROGRAMMING PERFORMANCE..................................................................................................... 43 DATA RETENTION..................................................................................................................................................... 43 LATCH-UP CHARACTERISTICS............................................................................................................................... 43 ORDERING INFORMATION....................................................................................................................................... 44 PART NAME DESCRIPTION...................................................................................................................................... 45 PACKAGE INFORMATION......................................................................................................................................... 46 REVISION HISTORY .................................................................................................................................................. 47 P/N: PM1553 4 REV. 1.6, DEC. 12, 2012 MX25L1635E 16M-BIT [x 1/x 2/x 4] CMOS SERIAL FLASH FEATURES General • Serial Peripheral Interface compatible -- Mode 0 and Mode 3 • 16,777,216 x 1 bit structure or 8,388,608 x 2 bits structure or 4,194,304 x 4 bits structure • 512 Equal Sectors with 4K byte each - Any Sector can be erased individually • 32 Equal Blocks with 64K byte each - Any Block can be erased individually • Single Power Supply Operation - 2.7 to 3.6 volt for read, erase, and program operations • Latch-up protected to 100mA from -1V to Vcc +1V Performance • High Performance - Fast read - 1 I/O: 108MHz with 8 dummy cycles - 2 I/O: 80MHz (Vcc=2.7V~3.6V); 104MHz (Vcc=3.0V~3.6V) with 4 dummy cycles - 4 I/O: 108MHz with 6 dummy cycles - Fast program time: 0.7ms(typ.) and 3ms(max.)/page (256-byte per page) - Byte program time: 9us (typical) - Fast erase time: 60ms (typ.)/sector (4K-byte per sector) ; 0.4s(typ.) /block (64K-byte per block); 6s(typ.) /chip • Low Power Consumption - Low active read current: 25mA(max.) at 108MHz and 10mA(max.) at 50MHz - Low active programming current: 20mA (max.) - Low active erase current: 20mA (max.) - Low standby current: 20uA (typ.); 50uA (max.) - Deep power down current: 3uA (typ.); 20uA (max.) • Typical 100,000 erase/program cycles • 20 years data retention Software Features • Input Data Format - 1-byte Command code • Advanced Security Features - Block lock protection The BP0-BP3 status bit defines the size of the area to be software protection against program and erase instructions - Additional 4K-bit secured OTP for unique identifier • Auto Erase and Auto Program Algorithm - Automatically erases and verifies data at selected sector - Automatically programs and verifies data at selected page by an internal algorithm that automatically times the program pulse widths (Any page to be programed should have page in the erased state first) • Status Register Feature • Electronic Identification - JEDEC 1-byte manufacturer ID and 2-byte device ID - RES command for 1-byte Device ID - All REMS, REMS2 and REMS4 commands for 1-byte manufacturer ID and 1-byte device ID P/N: PM1553 5 REV. 1.6, DEC. 12, 2012 MX25L1635E Hardware Features • SCLK Input - Serial clock input • SI/SIO0 - Serial Data Input or Serial Data Input/Output for 2 x I/O read mode and 4 x I/O read mode • SO/SIO1 - Serial Data Output or Serial Data Input/Output for 2 x I/O read mode and 4 x I/O read mode • WP#/SIO2 - Hardware write protection or serial data Input/Output for 4 x I/O read mode • NC/SIO3 - NC pin or serial data Input/Output for 4 x I/O read mode • PACKAGE - 8-pin SOP (200mil) - All devices are RoHS Compliant P/N: PM1553 6 REV. 1.6, DEC. 12, 2012 MX25L1635E GENERAL DESCRIPTION The MX25L1635E are 16,777,216 bit serial Flash memory, which is configured as 2,097,152 x 8 internally. When it is in four I/O read mode, the structure becomes 8,388,608 bits x 2 or 4,194,304 bits x 4. The MX25L1635E feature a serial peripheral interface and software protocol allowing operation on a simple 3-wire bus. The three bus signals are a clock input (SCLK), a serial data input (SI), and a serial data output (SO). Serial access to the device is enabled by CS# input. When it is in two I/O read mode, the SI pin and SO pin become SIO0 pin and SIO1 pin for address/dummy bits input and data output. When it is in four I/O read mode, the SI pin, SO pin, WP# pin and NC pin become SIO0 pin, SIO1 pin, SIO2 pin and SIO3 pin for address/dummy bits input and data output. The MX25L1635E provides sequential read operation on whole chip. After program/erase command is issued, auto program/ erase algorithms which program/ erase and verify the specified page or sector/block locations will be executed. Program command is executed on byte basis, or page (256 bytes) basis, or word basis for Continuously program mode, and erase command is executes on sector (4K-byte), or block (64K-byte), or whole chip basis. To provide user with ease of interface, a status register is included to indicate the status of the chip. The status read command can be issued to detect completion status of a program or erase operation via WIP bit. Secured OTP and Block Protection, please see security feature and write status register section for more details. When the device is not in operation and CS# is high, it is put in standby mode and draws less than 50uA DC current. Table 1. Additional Feature Comparison Protection and Security Additional Features Flexible Block 4K-bit Part Protection secured Name (BP0OTP BP3) MX25L1635E P/N: PM1553 V V Read Performance Identifier 1 I/O Read (108 MHz) 2 I/O Read (80MHz; 104MHz) 4 I/O Read (108 MHz) V V V RES REMS REMS2 REMS4 RDID (command: (command: (command: (command: (command: AB hex) 90 hex) EF hex) DF hex) 9F hex) 25 (hex) 7 C2 25 (hex) C2 25 (hex) (if ADD=0) (if ADD=0) C2 25 C2 25 15 (hex) (hex) (if ADD=0) REV. 1.6, DEC. 12, 2012 MX25L1635E PIN CONFIGURATIONS PIN DESCRIPTION 8-PIN SOP (200mil) CS# SO/SIO1 WP#/SIO2 GND 1 2 3 4 SYMBOL CS# 8 7 6 5 VCC NC/SIO3 SCLK SI/SIO0 SI/SIO0 SO/SIO1 SCLK WP#/SIO2 NC/SIO3 VCC GND P/N: PM1553 8 DESCRIPTION Chip Select Serial Data Input (for 1 x I/O) / Serial Data Input & Output (for 2xI/O or 4xI/O read mode) Serial Data Output (for 1 x I/O) Serial Data Input & Output (for 2xI/O or 4xI/O read mode) Clock Input Write protection: connect to GND or Serial Data Input & Output (for 4xI/O read mode) NC pin (Not connect) or Serial Data Input & Output (for 4xI/O read mode) + 3.3V Power Supply Ground REV. 1.6, DEC. 12, 2012 MX25L1635E BLOCK DIAGRAM X-Decoder Address Generator Memory Array Page Buffer SI/SIO0 Data Register Y-Decoder SRAM Buffer CS# WP#/SIO2 NC/SIO3 SCLK Mode Logic State Machine HV Generator Clock Generator Output Buffer SO/SIO1 P/N: PM1553 Sense Amplifier 9 REV. 1.6, DEC. 12, 2012 MX25L1635E DATA PROTECTION During power transition, there may be some false system level signals which result in inadvertent erasure or programming. The device is designed to protect itself from these accidental write cycles. The state machine will be reset as standby mode automatically during power up. In addition, the control register architecture of the device constrains that the memory contents can only be changed after specific command sequences have completed successfully. In the following, there are several features to protect the system from the accidental write cycles during VCC powerup and power-down or from system noise. • Valid command length checking: The command length will be checked whether it is at byte base and completed on byte boundary. • Write Enable (WREN) command: WREN command is required to set the Write Enable Latch bit (WEL) before other command to change data. The WEL bit will return to reset stage under following situation: - Power-up - Write Disable (WRDI) command completion - Write Status Register (WRSR) command completion - Page Program (PP) command completion - Page Program (4PP) command completion - Sector Erase (SE) command completion - Block Erase (BE) command completion - Chip Erase (CE) command completion • Deep Power Down Mode: By entering deep power down mode, the flash device also is under protected from writing all commands except Release from deep power down mode command (RDP) and Read Electronic Signature command (RES). • Advanced Security Features: there are some protection and security features which protect content from inadvertent write and hostile access. I. Block lock protection - The Software Protected Mode (SPM) use (BP3, BP2, BP1, BP0) bits to allow part of memory to be protected as read only. The protected area definition is shown as table of "Table 2. Protected Area Sizes", the protected areas are more flexible which may protect various area by setting value of BP0-BP3 bits. Please refer to table of "Table 2. Protected Area Sizes". - The Hardware Protected Mode (HPM) use WP#/SIO2 to protect the (BP3, BP2, BP1, BP0) bits and SRWD bit. If the system goes into four I/O read mode, the feature of HPM will be disabled. P/N: PM1553 10 REV. 1.6, DEC. 12, 2012 MX25L1635E Table 2. Protected Area Sizes Status bit Protect Level BP3 BP2 BP1 BP0 No. 16Mb 0 0 0 0 0 (none) 0 0 0 1 1 (1block, protected block 31th) 0 0 1 0 2 (2blocks, protected block 30th-31th) 0 0 1 1 3 (4blocks, protected block 28th-31th) 0 1 0 0 4 (8blocks, protected block 24th-31th) 0 1 0 1 5 (16blocks, protected block 16th-31th) 0 1 1 0 6 (32blocks, protected all) 0 1 1 1 7 (32blocks, protected all) 1 0 0 0 8 (32blocks, protected all) 1 0 0 1 9 (32blocks, protected all) 1 0 1 0 10 (16blocks, protected block 0th-15th) 1 0 1 1 11 (24blocks, protected block 0th-23th) 1 1 0 0 12 (28blocks, protected block 0th-27th) 1 1 0 1 13 (30blocks, protected block 0th-29th) 1 1 1 0 14 (31blocks, protected block 0th-30th) 1 1 1 1 15 (32blocks, protected all) II. Additional 4K-bit secured OTP for unique identifier: to provide 4K-bit One-Time Program area for setting device unique serial number - Which may be set by factory or system maker. Please refer to "Table 3. 4K-bit Secured OTP Definition". - Security register bit 0 indicates whether the chip is locked by factory or not. - To program the 4K-bit secured OTP by entering 4K-bit secured OTP mode (with ENSO command), and going through normal program procedure, and then exiting 4K-bit secured OTP mode by writing EXSO command. - Customer may lock-down the customer lockable secured OTP by writing WRSCUR(write security register) command to set customer lock-down bit1 as "1". Please refer to table of "Security Register Definition" for security register bit definition and "Table 3. 4K-bit Secured OTP Definition" for address range definition. - Note: Once lock-down whatever by factory or customer, it cannot be changed any more. While in 4K-bit Secured OTP mode, array access is not allowed. Table 3. 4K-bit Secured OTP Definition Address range Size Standard Factory Lock xxx000~xxx00F 128-bit ESN (electrical serial number) xxx010~xxx1FF 3968-bit N/A P/N: PM1553 11 Customer Lock Determined by customer REV. 1.6, DEC. 12, 2012 MX25L1635E Memory Organization Block Table 4. Memory Organization (16Mb) Block 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 P/N: PM1553 Sector 511 : 496 495 : 480 479 : 464 463 : 448 447 : 432 431 : 416 415 : 400 399 : 384 383 : 368 367 : 352 351 : 336 335 : 320 319 : 304 303 : 288 287 : 272 271 : 256 Address Range 1FF000h 1FFFFFh : : 1F0000h 1F0FFFh 1EF000h 1EFFFFh : : 1E0000h 1E0FFFh 1DF000h 1DFFFFh : : 1D0000h 1D0FFFh 1CF000h 1CFFFFh : : 1C0000h 1C0FFFh 1BF000h 1BFFFFh : : 1B0000h 1B0FFFh 1AF000h 1AFFFFh : : 1A0000h 1A0FFFh 19F000h 19FFFFh : : 190000h 190FFFh 18F000h 18FFFFh : : 180000h 180FFFh 17F000h 17FFFFh : : 170000h 170FFFh 16F000h 16FFFFh : : 160000h 160FFFh 15F000h 15FFFFh : : 150000h 150FFFh 14F000h 14FFFFh : : 140000h 140FFFh 13F000h 13FFFFh : : 130000h 130FFFh 12F000h 12FFFFh : : 120000h 120FFFh 11F000h 11FFFFh : : 110000h 110FFFh 10F000h 10FFFFh : : 100000h 100FFFh 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 12 Sector 255 : 240 239 : 224 223 : 208 207 : 192 191 : 176 175 : 160 159 : 144 143 : 128 127 : 112 111 : 96 95 : 80 79 : 64 63 : 48 47 : 32 31 : 16 15 : 2 1 0 Address Range 0FF000h 0FFFFFh : : 0F0000h 0F0FFFh 0EF000h 0EFFFFh : : 0E0000h 0E0FFFh 0DF000h 0DFFFFh : : 0D0000h 0D0FFFh 0CF000h 0CFFFFh : : 0C0000h 0C0FFFh 0BF000h 0BFFFFh : : 0B0000h 0B0FFFh 0AF000h 0AFFFFh : : 0A0000h 0A0FFFh 09F000h 09FFFFh : : 090000h 090FFFh 08F000h 08FFFFh : : 080000h 080FFFh 07F000h 07FFFFh : : 070000h 070FFFh 06F000h 06FFFFh : : 060000h 060FFFh 05F000h 05FFFFh : : 050000h 050FFFh 04F000h 04FFFFh : : 040000h 040FFFh 03F000h 03FFFFh : : 030000h 030FFFh 02F000h 02FFFFh : : 020000h 020FFFh 01F000h 01FFFFh : : 010000h 010FFFh 00F000h 00FFFFh : : 002000h 002FFFh 001000h 001FFFh 000000h 000FFFh REV. 1.6, DEC. 12, 2012 MX25L1635E DEVICE OPERATION 1. Before a command is issued, status register should be checked to ensure device is ready for the intended operation. 2. When incorrect command is inputted to this LSI, this LSI becomes standby mode and keeps the standby mode until next CS# falling edge. In standby mode, all SO pins of this LSI should be High-Z. 3. When correct command is inputted to this LSI, this LSI becomes active mode and keeps the active mode until next CS# rising edge. 4. Input data is latched on the rising edge of Serial Clock (SCLK) and data shifts out on the falling edge of SCLK. The difference of Serial mode 0 and mode 3 is shown as "Figure 1. Serial Modes Supported". 5. For the following instructions: RDID, RDSR, RDSCUR, READ, FAST_READ, 2READ, 4READ, RES, REMS, REMS2 and REMS4 the shifted-in instruction sequence is followed by a data-out sequence. After any bit of data being shifted out, the CS# can be high. For the following instructions: WREN, WRDI, WRSR, SE, BE, CE, PP, 4PP, CP, RDP, DP, ENSO, EXSO, and WRSCUR, the CS# must go high exactly at the byte boundary; otherwise, the instruction will be rejected and not executed. 6. During the progress of Write Status Register, Program, Erase operation, to access the memory array is neglected and not affect the current operation of Write Status Register, Program, Erase. Figure 1. Serial Modes Supported CPOL CPHA shift in (Serial mode 0) 0 0 SCLK (Serial mode 3) 1 1 SCLK SI shift out MSB SO MSB Note: CPOL indicates clock polarity of Serial master, CPOL=1 for SCLK high while idle, CPOL=0 for SCLK low while not transmitting. CPHA indicates clock phase. The combination of CPOL bit and CPHA bit decides which Serial mode is supported. P/N: PM1553 13 REV. 1.6, DEC. 12, 2012 MX25L1635E COMMAND DESCRIPTION Table 5. Command Set Command (byte) 1st byte 2nd byte 3rd byte 4th byte 5th byte Action Command (byte) 1st byte 2nd byte 3rd byte 4th byte Action 4READ RDSR WRSR FAST READ 2READ WRDI (write RDID (read READ (4 x I/O read (read status (write status (fast read (2 x I/O read disable) identification) (read data) command) register) register) data) command) Note1 06 (hex) 04 (hex) 9F (hex) 05 (hex) 01 (hex) 03 (hex) 0B (hex) BB (hex) EB (hex) AD1 ADD(4) & Values AD1 ADD(2) (A23-A16) Dummy(4) AD2 ADD(2) & AD2 Dummy(4) (A15-A8) Dummy(2) AD3 AD3 (A7-A0) Dummy sets the resets the outputs to read out to write new n bytes n bytes read n bytes n bytes (WEL) write (WEL) write JEDEC the values values of read out out until read out read out enable latch enable latch ID: 1-byte of the status the status until CS# CS# goes by 2 x I/O by 4 x I/O bit bit Manufacturer register register goes high high until CS# until CS# ID & 2-byte goes high goes high Device ID WREN (write enable) 4PP (quad page program) 38 (hex) AD1 SE (sector erase) 20 (hex) AD1 AD2 AD3 quad input to to erase the program the selected selected page sector REMS (read Commelectronic and (byte) manufacturer & device ID) 1st byte 90 (hex) 2nd byte X 3rd byte X 4th byte ADD (Note 2) output the Manufacturer ID & Device ID Action BE (block erase) CE (chip erase) PP (page program) D8 (hex) 60 or C7 (hex) 02 (hex) AD1 AD1 AD2 AD2 AD3 AD3 to erase the to erase to program selected whole chip the selected block page RDP (Release RES (read from deep electronic ID) power down) B9 (hex) AB (hex) AB (hex) X X X enters deep release from to read out power down deep power 1-byte Device mode down mode ID DP (Deep power down) REMS2 (read REMS4 (read RDSCUR WRSCUR ENSO (enter EXSO (exit Release Read ID for 2x I/O ID for 4x I/O (read security (write security secured OTP) secured OTP) Enhanced mode) mode) register) register) EF (hex) DF (hex) B1 (hex) C1 (hex) 2B (hex) 2F (hex) FF (hex) X X X X X X ADD (Note 2) ADD (Note 2) X output the output the to enter to set the All these to exit the 4K- to read value Manufacturer Manufacturer the 4K-bit of security lock-down bit commends bit secured ID & Device ID & Device secured OTP OTP mode register as "1" (once FFh, 00h, AAh ID ID lock-down, or 55h will mode cannot be escape the update) performance enhance mode Note 1: The count base is 4-bit for ADD(4) and Dummy(4) because of 4 x I/O. And the MSB is on SI/SIO1, WP#/SIO2 which is different from 1 x I/O condition. Note 2: ADD=00H will output the manufacturer ID first and ADD=01H will output device ID first. Note 3: It is not recommended to adopt any other code not in the command definition table, which will potentially enter the hidden mode. P/N: PM1553 14 REV. 1.6, DEC. 12, 2012 MX25L1635E (1) Write Enable (WREN) The Write Enable (WREN) instruction is for setting Write Enable Latch (WEL) bit. For those instructions like PP, 4PP, CP, SE, BE, CE, and WRSR, which are intended to change the device content, should be set every time after the WREN instruction setting the WEL bit. The sequence of issuing WREN instruction is: CS# goes low→ sending WREN instruction code→ CS# goes high. (Please refer to "Figure 9. Write Enable (WREN) Sequence (Command 06)") (2) Write Disable (WRDI) The Write Disable (WRDI) instruction is for resetting Write Enable Latch (WEL) bit. The sequence of issuing WRDI instruction is: CS# goes low→ sending WRDI instruction code→ CS# goes high. (Please refer to "Figure 10. Write Disable (WRDI) Sequence (Command 04)") The WEL bit is reset by following situations: - Power-up - Write Disable (WRDI) instruction completion - Write Status Register (WRSR) instruction completion - Page Program (PP) instruction completion - Quad Page Program (4PP) instruction completion - Sector Erase (SE) instruction completion - Block Erase (BE) instruction completion - Chip Erase (CE) instruction completion (3) Read Identification (RDID) The RDID instruction is for reading the manufacturer ID of 1-byte and followed by Device ID of 2-byte. Macronix Manufacturer ID is C2(hex), the memory type ID is 25(hex) as the first-byte device ID, and the individual device ID of second-byte ID are listed as "Table 7. ID Definitions". The sequence of issuing RDID instruction is: CS# goes low→ sending RDID instruction code→ 24-bits ID data out on SO→ to end RDID operation can use CS# to high at any time during data out. (Please refer to "Figure 11. Read Identification (RDID) Sequence (Command 9F)".) While Program/Erase operation is in progress, it will not decode the RDID instruction, so there's no effect on the cycle of program/erase operation which is currently in progress. When CS# goes high, the device is at standby stage. P/N: PM1553 15 REV. 1.6, DEC. 12, 2012 MX25L1635E (4) Read Status Register (RDSR) The RDSR instruction is for reading Status Register Bits. The Read Status Register can be read at any time (even in program/erase/write status register condition) and continuously. It is recommended to check the Write in Progress (WIP) bit before sending a new instruction when a program, erase, or write status register operation is in progress. The sequence of issuing RDSR instruction is: CS# goes low→ sending RDSR instruction code→ Status Register data out on SO (Please refer to "Figure 12. Read Status Register (RDSR) Sequence (Command 05)") The definition of the status register bits is as below: WIP bit. The Write in Progress (WIP) bit, a volatile bit, indicates whether the device is busy in program/erase/write status register progress. When WIP bit sets to 1, which means the device is busy in program/erase/write status register progress. When WIP bit sets to 0, which means the device is not in progress of program/erase/write status register cycle. WEL bit. The Write Enable Latch (WEL) bit, a volatile bit, indicates whether the device is set to internal write enable latch. When WEL bit sets to 1, which means the internal write enable latch is set, the device can accept program/ erase/write status register instruction. When WEL bit sets to 0, which means no internal write enable latch; the device will not accept program/erase/write status register instruction. The program/erase command will be ignored and not affect value of WEL bit if it is applied to a protected memory area. BP3, BP2, BP1, BP0 bits. The Block Protect (BP3, BP2, BP1, BP0) bits, non-volatile bits, indicate the protected area (as defined in table 2) of the device to against the program/erase instruction without hardware protection mode being set. To write the Block Protect (BP3, BP2, BP1, BP0) bits requires the Write Status Register (WRSR) instruction to be executed. Those bits define the protected area of the memory to against Page Program (PP), Sector Erase (SE), Block Erase (BE) and Chip Erase (CE) instructions (only if all Block Protect bits set to 0, the CE instruction can be executed). QE bit. The Quad Enable (QE) bit, non-volatile bit, performs Quad when it is reset to "0" (factory default) to enable WP# or is set to "1" to enable Quad SIO2 and SIO3. Once the system goes into Quad I/O mode, the feature of HPM will be disabled. SRWD bit. The Status Register Write Disable (SRWD) bit, non-volatile bit, which is set to "0" (factory default). The SRWD bit is operated together with Write Protection (WP#/SIO2) pin for providing hardware protection mode. The hardware protection mode requires SRWD sets to 1 and WP#/SIO2 pin signal is low stage. In the hardware protection mode, the Write Status Register (WRSR) instruction is no longer accepted for execution and the SRWD bit and Block Protect bits (BP3, BP2, BP1, BP0) are read only. Status Register bit7 bit6 SRWD (status register write protect) QE (Quad Enable) bit5 BP3 (level of protected block) bit4 BP2 (level of protected block) 1=Quad 1=status Enable register write (note 1) (note 1) 0=not Quad disable Enable Non-volatile Non-volatile Non-volatile Non-volatile bit bit bit bit Factory Factory Factory Factory default=0 default=0 default=0 default=0 Note 1: see the "Table 2. Protected Area Sizes". P/N: PM1553 bit3 BP1 (level of protected block) bit2 BP0 (level of protected block) (note 1) (note 1) Non-volatile bit Factory default=0 Non-volatile bit Factory default=0 16 bit1 bit0 WEL WIP (write enable (write in latch) progress bit) 1=write 1=write enable operation 0=not write 0=not in write enable operation volatile bit volatile bit Factory default=0 Factory default=0 REV. 1.6, DEC. 12, 2012 MX25L1635E (5) Write Status Register (WRSR) The WRSR instruction is for changing the values of Status Register Bits. Before sending WRSR instruction, the Write Enable (WREN) instruction must be decoded and executed to set the Write Enable Latch (WEL) bit in advance. The WRSR instruction can change the value of Block Protect (BP3, BP2, BP1, BP0) bits to define the protected area of memory (as shown in table 2). The WRSR also can set or reset the Quad enable (QE) bit and set or reset the Status Register Write Disable (SRWD) bit in accordance with Write Protection (WP#/SIO2) pin signal, but has no effect on bit1(WEL) and bit0 (WIP) of the status register. The WRSR instruction cannot be executed once the Hardware Protected Mode (HPM) is entered. The sequence of issuing WRSR instruction is: CS# goes low→ sending WRSR instruction code→ Status Register data on SI→ CS# goes high. (Please refer to "Figure 13. Write Status Register (WRSR) Sequence (Command 01)") The CS# must go high exactly at the byte boundary; otherwise, the instruction will be rejected and not executed. The self-timed Write Status Register cycle time (tW) is initiated as soon as Chip Select (CS#) goes high. The Write in Progress (WIP) bit still can be check out during the Write Status Register cycle is in progress. The WIP sets 1 during the tW timing, and sets 0 when Write Status Register Cycle is completed, and the Write Enable Latch (WEL) bit is reset. Table 6. Protection Modes Mode Status register condition WP# and SRWD bit status Memory Software protection mode (SPM) Status register can be WP#=1 and SRWD bit=0, or written in (WEL bit is set to The protected area cannot WP#=0 and SRWD bit=0, "1") and the SRWD, BP0be programmed or erased. WP#=1 and SRWD bit=1 BP1 bits can be changed Hardware protection mode (HPM) The SRWD, BP0-BP1 of status register bits can be changed WP#=0, SRWD bit=1 The protected area cannot be programmed or erased. Note: 1. As defined by the values in the Block Protect (BP3, BP2, BP1, BP0) bits of the Status Register. As the above table showing, the summary of the Software Protected Mode (SPM) and Hardware Protected Mode (HPM). Software Protected Mode (SPM): - When SRWD bit=0, no matter WP#/SIO2 is low or high, the WREN instruction may set the WEL bit and can change the values of SRWD, BP3, BP2, BP1, BP0. The protected area, which is defined by BP3, BP2, BP1, BP0, is at software protected mode (SPM). - When SRWD bit=1 and WP#/SIO2 is high, the WREN instruction may set the WEL bit can change the values of SRWD, BP3, BP2, BP1, BP0. The protected area, which is defined by BP3, BP2, BP1, BP0, is at software protected mode (SPM) Note: If SRWD bit=1 but WP#/SIO2 is low, it is impossible to write the Status Register even if the WEL bit has previously been set. It is rejected to write the Status Register and not be executed. P/N: PM1553 17 REV. 1.6, DEC. 12, 2012 MX25L1635E Hardware Protected Mode (HPM): - When SRWD bit=1, and then WP#/SIO2 is low (or WP#/SIO2 is low before SRWD bit=1), it enters the hardware protected mode (HPM). The data of the protected area is protected by software protected mode by BP3, BP2, BP1, BP0 and hardware protected mode by the WP#/SIO2 to against data modification. Note: To exit the hardware protected mode requires WP#/SIO2 driving high once the hardware protected mode is entered. If the WP#/SIO2 pin is permanently connected to high, the hardware protected mode can never be entered; only can use software protected mode via BP3, BP2, BP1, BP0. If the system goes into four I/O read mode, the feature of HPM will be disabled. (6) Read Data Bytes (READ) The read instruction is for reading data out. The address is latched on rising edge of SCLK, and data shifts out on the falling edge of SCLK at a maximum frequency fR. The first address can be at any location. The address is automatically increased to the next higher address after each byte data is shifted out, so the whole memory can be read out at a single READ instruction. The address counter rolls over to 0 when the highest address has been reached. The sequence of issuing READ instruction is: CS# goes low→ sending READ instruction code→ 3-byte address on SI→ data out on SO→ to end READ operation can use CS# to high at any time during data out. (Please refer to "Figure 14. Read Data Bytes (READ) Sequence (Command 03)") (7) Read Data Bytes at Higher Speed (FAST_READ) The FAST_READ instruction is for quickly reading data out. The address is latched on rising edge of SCLK, and data of each bit shifts out on the falling edge of SCLK at a maximum frequency fC. The first address can be at any location. The address is automatically increased to the next higher address after each byte data is shifted out, so the whole memory can be read out at a single FAST_READ instruction. The address counter rolls over to 0 when the highest address has been reached. The sequence of issuing FAST_READ instruction is: CS# goes low→ sending FAST_READ instruction code→3byte address on SI→ 1-dummy byte address on SI→data out on SO→to end FAST_READ operation can use CS# to high at any time during data out. (Please refer to "Figure 15. Read at Higher Speed (FAST_READ) Sequence (Command 0B)") While Program/Erase/Write Status Register cycle is in progress, FAST_READ instruction is rejected without any impact on the Program/Erase/Write Status Register current cycle. (8) 2 x I/O Read Mode (2READ) The 2READ instruction enable double throughput of Serial Flash in read mode. The address is latched on rising edge of SCLK, and data of every two bits (interleave on 2 I/O pins) shift out on the falling edge of SCLK at a maximum frequency fT. The first address can be at any location. The address is automatically increased to the next higher address after each byte data is shifted out, so the whole memory can be read out at a single 2READ instruction. The address counter rolls over to 0 when the highest address has been reached. Once writing 2READ instruction, the following address/dummy/data out will perform as 2-bit instead of previous 1-bit. The sequence of issuing 2READ instruction is: CS# goes low→ sending 2READ instruction→ 24-bit address interleave on SIO1 & SIO0→4 dummy cycles on SIO1 & SIO0→data out interleave on SIO1 & SIO0→ to end 2READ operation can use CS# to high at any time during data out (see "Figure 16. 2 x I/O Read Mode Sequence (Command BB)"). While Program/Erase/Write Status Register cycle is in progress, 2READ instruction is rejected without any impact on the Program/Erase/Write Status Register current cycle. P/N: PM1553 18 REV. 1.6, DEC. 12, 2012 MX25L1635E (9) 4 x I/O Read Mode (4READ) The 4READ instruction enable quad throughput of Serial Flash in read mode. A Quad Enable (QE) bit of status Register must be set to "1" before sending the 4READ instruction. The address is latched on rising edge of SCLK, and data of every four bits (interleave on 4 I/O pins) shift out on the falling edge of SCLK at a maximum frequency fQ. The first address can be at any location. The address is automatically increased to the next higher address after each byte data is shifted out, so the whole memory can be read out at a single 4READ instruction. The address counter rolls over to 0 when the highest address has been reached. Once writing 4READ instruction, the following address/dummy/data out will perform as 4-bit instead of previous 1-bit. The sequence of issuing 4READ instruction is: CS# goes low→sending 4READ instruction→ 24-bit address interleave on SIO3, SIO2, SIO1 & SIO0→ 6 dummy cycles → data out interleave on SIO3, SIO2, SIO1 & SIO0→ to end 4READ operation can use CS# to high at any time during data out (see "Figure 18. 4 x I/O Read enhance performance Mode Sequence (Command EB)"). Another sequence of issuing 4 READ instruction especially useful in random access is: CS# goes low→sending 4 READ instruction→24-bit address interleave on SIO3, SIO2, SIO1 & SIO0 →performance enhance toggling bit P[7:0]→ 4 dummy cycles →data out interleave on SIO3, SIO2, SIO1 and SIO0 till CS# goes high → CS# goes low (reduce 4 Read instruction) →24-bit random access address (see "Figure 18. 4 x I/O Read enhance performance Mode Sequence (Command EB)"). In the performance-enhancing mode (Note of Figure. 17), P[7:4] must be toggling with P[3:0] ; likewise P[7:0]=A5h,5Ah,F0h or 0Fh can make this mode continue and reduce the next 4READ instruction. Once P[7:4] is no longer toggling with P[3:0]; likewise P[7:0]=FFh,00h,AAh or 55h and afterwards CS# is raised and then lowered, the system then will escape from performance enhance mode and return to normal operation. While Program/Erase/Write Status Register cycle is in progress, 4READ instruction is rejected without any impact on the Program/Erase/Write Status Register current cycle. (10) Sector Erase (SE) The Sector Erase (SE) instruction is for erasing the data of the chosen sector to be "1". The instruction is used for any 4K-byte sector. A Write Enable (WREN) instruction must execute to set the Write Enable Latch (WEL) bit before sending the Sector Erase (SE). Any address of the sector (see table 4) is a valid address for Sector Erase (SE) instruction. The CS# must go high exactly at the byte boundary (the eighth bit of last address byte been latched-in); otherwise, the instruction will be rejected and not executed. Address bits [Am-A12] (Am is the most significant address) select the sector address. The sequence of issuing SE instruction is: CS# goes low→ sending SE instruction code→ 3-byte address on SI → CS# goes high. (Please refer to "Figure 21. Sector Erase (SE) Sequence (Command 20)") The self-timed Sector Erase Cycle time (tSE) is initiated as soon as Chip Select (CS#) goes high. The Write in Progress (WIP) bit still can be check out during the Sector Erase cycle is in progress. The WIP sets 1 during the tSE timing, and sets 0 when Sector Erase Cycle is completed, and the Write Enable Latch (WEL) bit is reset. If the page is protected by BP3, BP2, BP1, BP0 bits, the Sector Erase (SE) instruction will not be executed on the page. P/N: PM1553 19 REV. 1.6, DEC. 12, 2012 MX25L1635E (11) Block Erase (BE) The Block Erase (BE) instruction is for erasing the data of the chosen block to be "1". The instruction is used for 64K-byte block erase operation. A Write Enable (WREN) instruction must execute to set the Write Enable Latch (WEL) bit before sending the Block Erase (BE). Any address of the block (see "Table 4. Memory Organization (16Mb)") is a valid address for Block Erase (BE) instruction. The CS# must go high exactly at the byte boundary (the eighth bit of address byte been latched-in); otherwise, the instruction will be rejected and not executed. The sequence of issuing BE instruction is: CS# goes low→ sending BE instruction code→ 3-byte address on SI → CS# goes high. (Please refer to "Figure 22. Block Erase (BE) Sequence (Command D8)") The self-timed Block Erase Cycle time (tBE) is initiated as soon as Chip Select (CS#) goes high. The Write in Progress (WIP) bit still can be check out during the Sector Erase cycle is in progress. The WIP sets 1 during the tBE timing, and sets 0 when Sector Erase Cycle is completed, and the Write Enable Latch (WEL) bit is reset. If the page is protected by BP3, BP2, BP1, BP0 bits, the Block Erase (BE) instruction will not be executed on the page. (12) Chip Erase (CE) The Chip Erase (CE) instruction is for erasing the data of the whole chip to be "1". A Write Enable (WREN) instruction must execute to set the Write Enable Latch (WEL) bit before sending the Chip Erase (CE). The CS# must go high exactly at the byte boundary (the eighth bit of address byte been latched-in), otherwise the instruction will be rejected and not executed. The sequence of issuing CE instruction is: CS# goes low→ sending CE instruction code→ CS# goes high. (Please refer to "Figure 23. Chip Erase (CE) Sequence (Command 60 or C7)") The self-timed Chip Erase Cycle time (tCE) is initiated as soon as Chip Select (CS#) goes high. The Write in Progress (WIP) bit still can be check out during the Chip Erase cycle is in progress. The WIP sets 1 during the tCE timing, and sets 0 when Chip Erase Cycle is completed, and the Write Enable Latch (WEL) bit is reset. If the chip is protected by BP3, BP2, BP1, BP0 bits, the Chip Erase (CE) instruction will not be executed. It will be only executed when BP3, BP2, BP1, BP0 all set to "0". (13) Page Program (PP) The Page Program (PP) instruction is for programming the memory to be "0". A Write Enable (WREN) instruction must execute to set the Write Enable Latch (WEL) bit before sending the Page Program (PP). The device programs only the last 256 data bytes sent to the device. The last address byte (the 8 least significant address bits, A7-A0) should be set to 0 for 256 bytes page program. If A7-A0 are not all zero, transmitted data that exceed page length are programmed from the starting address (24-bit address that last 8 bit are all 0) of currently selected page. If the data bytes sent to the device exceeds 256, the last 256 data byte is programmed at the request page and previous data will be disregarded. If the data bytes sent to the device has not exceeded 256, the data will be programmed at the request address of the page. There will be no effort on the other data bytes of the same page. The sequence of issuing PP instruction is: CS# goes low→ sending PP instruction code→ 3-byte address on SI→ at least 1-byte on data on SI→ CS# goes high. (Please refer to "Figure 19. Page Program (PP) Sequence (Command 02)") The CS# must be kept to low during the whole Page Program cycle; The CS# must go high exactly at the byte boundary( the eighth bit of data being latched in), otherwise the instruction will be rejected and will not be executed. The self-timed Page Program Cycle time (tPP) is initiated as soon as Chip Select (CS#) goes high. The Write in P/N: PM1553 20 REV. 1.6, DEC. 12, 2012 MX25L1635E Progress (WIP) bit still can be check out during the Page Program cycle is in progress. The WIP sets 1 during the tPP timing, and sets 0 when Page Program Cycle is completed, and the Write Enable Latch (WEL) bit is reset. If the page is protected by BP3, BP2, BP1, BP0 bits, the Page Program (PP) instruction will not be executed. (14) 4 x I/O Page Program (4PP) The Quad Page Program (4PP) instruction is for programming the memory to be "0". A Write Enable (WREN) instruction must execute to set the Write Enable Latch (WEL) bit and Quad Enable (QE) bit must be set to "1" before sending the Quad Page Program (4PP). The Quad Page Programming takes four pins: SIO0, SIO1, SIO2, and SIO3, which can raise programer performance and and the effectiveness of application of lower clock less than 85MHz. For system with faster clock, the Quad page program cannot provide more actual favors, because the required internal page program time is far more than the time data flows in. Therefore, we suggest that while executing this command (especially during sending data), user can slow the clock speed down to 85MHz below. The other function descriptions are as same as standard page program. The sequence of issuing 4PP instruction is: CS# goes low→ sending 4PP instruction code→ 3-byte address on SIO[3:0]→ at least 1-byte on data on SIO[3:0]→ CS# goes high. (Please refer to "Figure 20. 4 x I/O Page Program (4PP) Sequence (Command 38)") (15) Deep Power-down (DP) The Deep Power-down (DP) instruction is for setting the device on the minimizing the power consumption (to entering the Deep Power-down mode), the standby current is reduced from ISB1 to ISB2). The Deep Power-down mode requires the Deep Power-down (DP) instruction to enter, during the Deep Power-down mode, the device is not active and all Write/Program/Erase instruction are ignored. When CS# goes high, it's only in standby mode not deep power-down mode. It's different from Standby mode. The sequence of issuing DP instruction is: CS# goes low→sending DP instruction code→CS# goes high. (Please refer to "Figure 24. Deep Power-down (DP) Sequence (Command B9)") Once the DP instruction is set, all instruction will be ignored except the Release from Deep Power-down mode (RDP) and Read Electronic Signature (RES) instruction. (those instructions allow the ID being reading out). When Powerdown, the deep power-down mode automatically stops, and when power-up, the device automatically is in standby mode. For RDP instruction the CS# must go high exactly at the byte boundary (the latest eighth bit of instruction code been latched-in); otherwise, the instruction will not executed. As soon as Chip Select (CS#) goes high, a delay of tDP is required before entering the Deep Power-down mode. (16) Release from Deep Power-down (RDP), Read Electronic Signature (RES) The Release from Deep Power-down (RDP) instruction is terminated by driving Chip Select (CS#) High. When Chip Select (CS#) is driven High, the device is put in the Stand-by Power mode. If the device was not previously in the Deep Power-down mode, the transition to the Stand-by Power mode is immediate. If the device was previously in the Deep Power-down mode, though, the transition to the Stand-by Power mode is delayed by tRES2, and Chip Select (CS#) must remain High for at least tRES2(max), as specified in "Table 10. AC Characteristics". Once in the Stand-by Power mode, the device waits to be selected, so that it can receive, decode and execute instructions. The RDP instruction is only for releasing from Deep Power Down Mode. RES instruction is for reading out the old style of 8-bit Electronic Signature, whose values are shown as table of ID Definitions in next page. This is not the same as RDID instruction. It is not recommended to use for new design. P/N: PM1553 21 REV. 1.6, DEC. 12, 2012 MX25L1635E For new design, please use RDID instruction. The sequence is shown as "Figure 25. Read Electronic Signature (RES) Sequence (Command AB)", "Figure 26. Release from Deep Power-down (RDP) Sequence (Command AB)". Even in Deep power-down mode, the RDP and RES are also allowed to be executed, only except the device is in progress of program/erase/write cycle; there's no effect on the current program/erase/write cycle in progress. The RES instruction is ended by CS# goes high after the ID been read out at least once. The ID outputs repeatedly if continuously send the additional clock cycles on SCLK while CS# is at low. If the device was not previously in Deep Power-down mode, the device transition to standby mode is immediate. If the device was previously in Deep Power-down mode, there's a delay of tRES2 to transit to standby mode, and CS# must remain to high at least tRES2(max). Once in the standby mode, the device waits to be selected, so it can be receive, decode, and execute instruction. (17) Read Electronic Manufacturer ID & Device ID (REMS), (REMS2), (REMS4) The REMS, REMS2 & REMS4 instruction is an alternative to the Release from Power-down/Device ID instruction that provides both the JEDEC assigned manufacturer ID and the specific device ID. The REMS4 instruction is recommended to use for 4 I/O identification and REMS2 instruction is recommended to use for 2 I/O identification. The REMS, REMS2 & REMS4 instruction is very similar to the Release from Power-down/Device ID instruction. The instruction is initiated by driving the CS# pin low and shift the instruction code "90h" or "EFh" or "DFh" followed by two dummy bytes and one bytes address (A7~A0). After which, the Manufacturer ID for Macronix (C2h) and the Device ID are shifted out on the falling edge of SCLK with most significant bit (MSB) first as shown in "Figure 27. Read Electronic Manufacturer & Device ID (REMS) Sequence (Command 90 or EF or DF)". The Device ID values are listed in Table 7 of ID Definitions in next page. If the one-byte address is initially set to 01h, then the device ID will be read first and then followed by the Manufacturer ID. The Manufacturer and Device IDs can be read continuously, alternating from one to the other. The instruction is completed by driving CS# high. Table 7. ID Definitions RDID Command manufacturer ID C2 memory type 25 electronic ID 25 device ID 25 RES Command REMS/REMS2/REMS4 Command P/N: PM1553 manufacturer ID C2 22 memory density 15 REV. 1.6, DEC. 12, 2012 MX25L1635E (18) Enter Secured OTP (ENSO) The ENSO instruction is for entering the additional 4K-bit secured OTP mode. The additional 4K-bit secured OTP is independent from main array, which may use to store unique serial number for system identifier. After entering the Secured OTP mode, and then follow standard read or program, procedure to read out the data or update data. The Secured OTP data cannot be updated again once it is lock-down. The sequence of issuing ENSO instruction is: CS# goes low→ sending ENSO instruction to enter Secured OTP mode→ CS# goes high. Please note that WRSR/WRSCUR commands are not acceptable during the access of secure OTP region, once security OTP is lock down, only read related commands are valid. (19) Exit Secured OTP (EXSO) The EXSO instruction is for exiting the additional 4K-bit secured OTP mode. The sequence of issuing EXSO instruction is: CS# goes low→sending EXSO instruction to exit Secured OTP mode→ CS# goes high. (20) Read Security Register (RDSCUR) The RDSCUR instruction is for reading the value of Security Register bits. The Read Security Register can be read at any time (even in program/erase/write status register/write security register condition) and continuously. The sequence of issuing RDSCUR instruction is : CS# goes low→ sending RDSCUR instruction →Security Register data out on SO→ CS# goes high. The definition of the Security Register bits is as below: Secured OTP Indicator bit. The Secured OTP indicator bit shows the chip is locked by factory before ex- factory or not. When it is "0", it indicates non-factory lock; "1" indicates factory- lock. Lock-down Secured OTP (LDSO) bit. By writing WRSCUR instruction, the LDSO bit may be set to "1" for customer lock-down purpose. However, once the bit is set to "1" (lock-down), the LDSO bit and the 4K-bit Secured OTP area cannot be update any more. While it is in 4K-bit secured OTP mode, main array access is not allowed. P/N: PM1553 23 REV. 1.6, DEC. 12, 2012 MX25L1635E (21) Write Security Register (WRSCUR) The WRSCUR instruction is for changing the values of Security Register Bits. Unlike write status register, the WREN instruction is not required before sending WRSCUR instruction. The WRSCUR instruction may change the values of bit1 (LDSO bit) for customer to lock-down the 4K-bit Secured OTP area. Once the LDSO bit is set to "1", the Secured OTP area cannot be updated any more. The sequence of issuing WRSCUR instruction is :CS# goes low→ sending WRSCUR instruction → CS# goes high. The CS# must go high exactly at the boundary; otherwise, the instruction will be rejected and not executed. Table 8. Security Register Definition bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 x x x x x x LDSO (indicate if lock-down Secured OTP indicator bit 0 = nonfactory lock 1 = factory lock non-volatile bit reserved reserved reserved reserved reserved reserved 0 = not lockdown 1 = lock-down (cannot program/erase OTP) volatile bit volatile bit volatile bit volatile bit volatile bit volatile bit non-volatile bit P/N: PM1553 24 REV. 1.6, DEC. 12, 2012 MX25L1635E POWER-ON STATE The device is at below states when power-up: - Standby mode ( please note it is not deep power-down mode) - Write Enable Latch (WEL) bit is reset The device must not be selected during power-up and power-down stage unless the VCC achieves below correct level: - VCC minimum at power-up stage and then after a delay of tVSL - GND at power-down Please note that a pull-up resistor on CS# may ensure a safe and proper power-up/down level. An internal power-on reset (POR) circuit may protect the device from data corruption and inadvertent data change during power up state. For further protection on the device, if the VCC does not reach the VCC minimum level, the correct operation is not guaranteed. The read, write, erase, and program command should be sent after the time delay: - tVSL after VCC reached VCC minimum level The device can accept read command after VCC reached VCC minimum and a time delay of tVSL. Please refer to the figure of "power-up timing". Note: - To stabilize the VCC level, the VCC rail decoupled by a suitable capacitor close to package pins is recommended. (generally around 0.1uF) P/N: PM1553 25 REV. 1.6, DEC. 12, 2012 MX25L1635E ELECTRICAL SPECIFICATIONS Absolute Maximum Ratings Rating Value Industrial grade Ambient Operating Temperature Storage Temperature -40°C to 85°C -55°C to 125°C Applied Input Voltage -0.5V to 4.6V Applied Output Voltage -0.5V to 4.6V VCC to Ground Potential -0.5V to 4.6V NOTICE: 1. Stresses greater than those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is stress rating only and functional operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended period may affect reliability. 2. Specifications contained within the following tables are subject to change. 3. During voltage transitions, all pins may overshoot Vss to -2.0V and Vcc to +2.0V for periods up to 20ns, see "Figure 2. Maximum Negative Overshoot Waveform", "Figure 3. Maximum Positive Overshoot Waveform". Figure 3. Maximum Positive Overshoot Waveform Figure 2. Maximum Negative Overshoot Waveform 20ns 20ns 20ns Vss Vcc + 2.0V Vss-2.0V Vcc 20ns 20ns 20ns Capacitance TA = 25°C, f = 1.0 MHz Symbol Parameter CIN COUT P/N: PM1553 Min. Typ. Max. Unit Input Capacitance 6 pF VIN = 0V Output Capacitance 8 pF VOUT = 0V 26 Conditions REV. 1.6, DEC. 12, 2012 MX25L1635E Figure 4. Input Test Waveforms and Measurement Level Input timing reference level 0.8VCC 0.2VCC 0.7VCC 0.3VCC Output timing reference level AC Measurement Level 0.5VCC Note: Input pulse rise and fall time are