A25L032

A25L016 Series 16Mbit Low Voltage, Serial Flash Memory With 100MHz Uniform 4KB Sectors Document Title 16Mbit, Low Voltage, Serial Flash Memory With 100MHz Uniform 4KB Sectors Revision History Rev. No. 0.0 History Initial issue Issue Date April 2, 2008 Remark Final (April, 2008, Version 0.0) AMIC Technology Corp. A25L016 Series 16Mbit Low Voltage, Serial Flash Memory With 100MHz Uniform 4KB Sectors FEATURES Family of Serial Flash Memories - A25L016: 16M-bit /2M-byte Flexible Sector Architecture with 4KB sectors - Sector Erase (4K-bytes) in 60ms (typical) - Block Erase (64K-bytes) in 0.5s (typical) Page Program (up to 256 Bytes) in 0.8ms (typical) 2.7 to 3.6V Single Supply Voltage Dual input / output instructions resulting in an equivalent clock frequency of 200MHz: - Dual Output Fast Read Instruction - Dual Input and Output Fast Read Instruction SPI Bus Compatible Serial Interface 100MHz Clock Rate (maximum) Deep Power-down Mode 5µA (Max) 16Mbit Flash memory - Uniform 4-Kbyte sectors - Uniform 64-Kbyte blocks Electronic Signatures - JEDEC Standard Two-Byte Signature A25L016: (3015h) - RES Instruction, One-Byte, Signature, for backward compatibility A25L016 (14h) Package options - 8-pin SOP (209mil), 16-pin SOP (300mil), 8-pin DIP (300mil) - All Pb-free (Lead-free) products are RoHS compliant GENERAL DESCRIPTION The A25L016 is 16M bit 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 32 blocks, each containing 16 sectors. Each sector is composed of 16 pages. Each page is 256 bytes wide. Thus, the whole memory can be viewed as consisting of 8,192 pages, or 2,097,152 bytes. The whole memory can be erased using the Chip Erase instruction, a block at a time, using Block Erase instruction, or a sector at a time, using the Sector Erase instruction. Pin Configurations SOP8 Connections SOP16 Connections A25L016 A25L016 HOLD VCC DU DU DU DU S DO 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 C DIO DU DU DU DU VSS W A25L016 S DO W VSS 1 2 3 4 8 VCC 7 HOLD 6C 5 DIO DIP8 Connections S DO W VSS 1 2 3 4 8 VCC 7 HOLD 6C 5 DIO Note: DU = Do not Use (April, 2008, Version 0.0) 1 AMIC Technology Corp. A25L016 Series Block Diagram HOLD W S C DIO DO I/O Shift Register Control Logic High Voltage Generator Address register and Counter 256 Byte Data Buffer Status Register 1FFFFF Y Decoder Size of the memory area 000FFh 00000h 256 Byte (Page Size) X Decoder Pin Descriptions Pin No. C DIO DO Serial Clock Serial Data Input 1 Serial Data Output 2 Chip Select Write Protect Hold Supply Voltage Ground Description Logic Symbol VCC DIO C S W HOLD A25L016 DO S W HOLD VCC VSS VSS Notes: 1. The DIO is also used as an output pin when the Fast Read Dual Output instruction and the Fast Read Dual Input-Output instruction are executed. 2. The DO is also used as an input pin when the Fast Read Dual Input-Output instruction. (April, 2008, Version 0.0) 2 AMIC Technology Corp. A25L016 Series SIGNAL DESCRIPTION Serial Data Output (DO). 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). The DO pin is also used as an input pin when the Fast Read Dual Input-Output instruction and Dual Input Fast Program is executed. Serial Data Input (DIO). 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). The DIO pin is also used as an output pin when the Fast Read Dual Output instruction and the Fast Read Dual Input-Output instruction are executed. Serial Clock (C). This input signal provides the timing of the serial interface. Instructions, addresses, or data present at Serial Data Input (DIO) are latched on the rising edge of Serial Clock (C). Data on Serial Data Output (DO) 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 (DO) 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 (DO) is high impedance, and Serial Data Input (DIO) 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). (April, 2008, Version 0.0) 3 AMIC Technology Corp. A25L016 Series 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 2, 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 1. Bus Master and Memory Devices on the SPI Bus SPI Interface with (CPOL, CPHA) = (0, 0) or (1, 1) Bus Master (ST6, ST7, ST9, ST10, Other) SDO SDI SCK C DO DIO C DO DIO C DO DIO SPI Memory Device CS3 CS2 CS1 S W HOLD SPI Memory Device SPI Memory Device S W HOLD S W HOLD Note: The Write Protect ( W ) and Hold ( HOLD ) signals should be driven, High or Low as appropriate. Figure 2. SPI Modes Supported CPOL 0 1 CPHA 0 1 C C DIO DO MSB MSB (April, 2008, Version 0.0) 4 AMIC Technology Corp. A25L016 Series 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. 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, TB, BP2, BP1, BP0) become read-only bits. Sector Erase, Block Erase, and Chip Erase The Page Program (PP) instruction and Dual Input Fast Program (DIFP) instruction allow bits to be reset from 1 to 0. Before this can be applied, the bytes of memory need to have been erased to all 1s (FFh). This can be achieved, a sector at a time, using the Sector Erase (SE) instruction, a block at a time, using the Block Erase (BE) instruction, or throughout the entire memory, using the Chip Erase (CE) instruction. This starts an internal Erase cycle (of duration tSE, tBE, or tCE). The Erase instruction must be preceded by a Write Enable (WREN) instruction. 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 A25L016 boasts the following data protection mechanisms: Power-On Reset and an internal timer (tPUW) can provide protection against inadvertent 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: - Power-up - Write Disable (WRDI) instruction completion - Write Status Register (WRSR) instruction completion - Page Program (PP) instruction completion - Sector Erase (SE) instruction completion - Block Erase (BE) instruction completion - Chip Erase (CE) instruction completion The Block Protect (BP2, BP1, BP0) bits allow part of the memory to be configured as read-only. This is the Software Protected Mode (SPM). 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 inadvertent Write, Program and Erase instructions, as all instructions are ignored except one particular instruction (the Release from Deep Power-down instruction). Polling During a Write, Program or Erase Cycle A further improvement in the time to Write Status Register (WRSR), Program (PP) or Erase (SE, BE, or CE) can be achieved by not waiting for the worst case delay (tW, tPP, tSE, tBE, tCE). The Write In Progress (WIP) bit is provided in the Status Register so that the application program can monitor its value, polling it to establish when the previous Write cycle, Program cycle or Erase cycle is complete. Active Power, Stand-by Power and Deep Power-Down Modes When Chip Select ( 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 ICC1. The Deep Power-down mode is entered when the specific instruction (the 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 inadvertent Write, Program or Erase instructions. Status Register The Status Register contains a number of status and control bits that can be read or set (as appropriate) by specific instructions. (April, 2008, Version 0.0) 5 AMIC Technology Corp. A25L016 Series Table 1. Protected Area Sizes Status Register Content BP2 BP1 BP0 Block(s) Memory Protection Addresses Density Portion 0 0 0 0 1 1 1 0 0 1 1 0 0 1 0 1 0 1 0 1 X None 31 30 – 31 28 – 31 24 – 31 16 – 31 0 – 31 None 1F0000h – 1FFFFFh 1E0000h – 1FFFFFh 1C0000h – 1FFFFFh 180000h – 1FFFFFh 100000h – 1FFFFFh 000000h – 1FFFFFh None 64KB 128KB 256KB 512KB 1MB 2MB None Upper 1/32 Upper 1/16 Upper 1/8 Upper 1/4 Upper 1/2 All Note: 1. X = don’t care 2. The device is ready to accept a Chip Erase instruction if, and only if, all Block Protect (BP2, BP1, BP0) are 0. (April, 2008, Version 0.0) 6 AMIC Technology Corp. A25L016 Series 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 3.). 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 3. During the Hold condition, the Serial Data Output (DO) is high impedance, and Serial Data Input (DIO) 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 3. Hold Condition Activation C HOLD Hold Condition (standard use) Hold Condition (non-standard use) (April, 2008, Version 0.0) 7 AMIC Technology Corp. A25L016 Series MEMORY ORGANIZATION The memory is organized as: 2,097,152 bytes (8 bits each) 32 blocks (64 Kbytes each) 512 sectors (4 Kbytes each) 8192 pages (256 bytes each) Each page can be individually programmed (bits are programmed from 1 to 0). The device is Sector, Block, or Chip Erasable (bits are erased from 0 to 1) but not Page Erasable. Table 2. Memory Organization A25L016 Address Table Block Sector Address range Block Sector Address range 511 ... 1FF000h ... 1FFFFFh ... 335 20 ... 14F000h ... 14FFFFh ... 31 496 495 ... 1F0000h 1EF000h ... 1F0FFFh 1EFFFFh ... 320 19 319 ... 140000h 13F000h ... 140FFFh 13FFFFh ... 30 480 479 29 464 463 28 448 447 27 432 431 26 416 415 25 400 399 24 384 383 23 368 367 22 352 351 21 336 ... ... ... ... ... ... ... ... ... 1E0000h 1DF000h 1D0000h 1CF000h 1C0000h 1BF000h 1B0000h 1AF000h 1A0000h 19F000h 190000h 18F000h 180000h 17F000h 170000h 16F000h 160000h 15F000h 150000h ... ... ... ... ... ... ... ... ... 1E0FFFh 1DFFFFh 1D0FFFh 1CFFFFh 1C0FFFh 1BFFFFh 1B0FFFh 1AFFFFh 1A0FFFh 19FFFFh 190FFFh 18FFFFh 180FFFh 17FFFFh 170FFFh 16FFFFh 160FFFh 15FFFFh 150FFFh ... ... ... ... ... ... ... ... ... 304 303 18 288 287 17 272 271 16 256 255 15 240 239 14 224 223 13 208 207 12 192 191 11 176 175 10 160 ... ... ... ... ... ... ... ... ... 130000h 12F000h 120000h 11F000h 110000h 10F000h 100000h FF000h F0000h EF000h E0000h DF000h D0000h CF000h C0000h BF000h B0000h AF000h A0000h ... ... ... ... ... ... ... ... ... 130FFFh 12FFFFh 120FFFh 11FFFFh 110FFFh 10FFFFh 100FFFh FFFFFh F0FFFh EFFFFh E0FFFh DFFFFh D0FFFh CFFFFh C0FFFh BFFFFh B0FFFh AFFFFh A0FFFh ... ... ... ... ... ... ... ... ... (April, 2008, Version 0.0) 8 AMIC Technology Corp. A25L016 Series Memory Organization (continued) Block Sector Address range Block Sector Address range 159 9 144 8 143 128 127 7 112 111 6 ... ... ... ... 9F000h 90000h 8F000h 80000h 7F000h 70000h 6F000h ... ... ... ... 9FFFFh 3 90FFFh 8FFFFh 2 80FFFh 7FFFFh 1 70FFFh 6FFFFh ... ... ... ... 63 ... 3F000h ... 3FFFFh ... 48 47 ... 30000h 2F000h ... 30FFFh 2FFFFh ... 32 31 ... 20000h 1F000h ... 20FFFh 1FFFFh ... 16 15 ... 10000h 0F000h ... 10FFFh 0FFFFh ... 96 95 5 ... 60000h 5F000h ... 60FFFh 5FFFFh ... 4 3 0 2 1 0 04000h 03000h 02000h 01000h 00000h 04FFFh 03FFFh 02FFFh 01FFFh 00FFFh 80 4 79 ... 50000h 4F000h ... 50FFFh 4FFFFh ... 64 40000h 40FFFh (April, 2008, Version 0.0) 9 AMIC Technology Corp. A25L016 Series INSTRUCTIONS All instructions, addresses and data are shifted in and out of the device, most significant bit first. Serial Data Input (DIO) 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 (DIO), each bit being latched on the rising edges of Serial Clock (C). The instruction set is listed in Table 3. 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. In the case of a Read Data Bytes (READ), Read Data Bytes at Higher Speed (Fast_Read), Read Identification (RDID), Read Electronic Manufacturer and Device Identification (REMS), Read Status Register (RDSR) or Release from Deep Power-down, Read Device Identification 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), Block Erase (BE), Chip Erase (CE), 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 3. Instruction Set Instruction Description One-byte Instruction Code Address Bytes Dummy Bytes Data Bytes WREN WRDI RDSR WRSR READ FAST_READ FAST_READ_DUAL _OUTPUT FAST_READ_DUAL _INPUT-OUTPUT PP SE BE CE DP RDID REMS Write Enable Write Disable Read Status Register Write Status Register Read Data Bytes Read Data Bytes at Higher Speed Read Data Bytes at Higher Speed by Dual Output (1) Read Data Bytes at Higher Speed by Dual Input and Dual Output (1) Page Program Sector Erase Block Erase Chip Erase Deep Power-down Read Device Identification Read Electronic Manufacturer & Device Identification Release from Deep Power-down, and Read Electronic Signature Release from Deep Power-down 0000 0110 0000 0100 0000 0101 0000 0001 0000 0011 0000 1011 00111011 10111011 0000 0010 0010 0000 1101 1000 1100 0111 1011 1001 1001 1111 1001 0000 06h 04h 05h 01h 03h 0Bh 3Bh BBh 02h 20h D8h C7h B9h 9Fh 90h 0 0 0 0 3 3 3 3(2) 3 3 3 0 0 0 1 (3) 0 0 0 0 0 1 1 1(2) 0 0 0 0 0 0 2 3 0 0 0 1 to ∞ 1 1 to ∞ 1 to ∞ 1 to ∞ 1 to ∞ 1 to 256 0 0 0 0 1 to ∞ 1 to ∞ 1 to ∞ 0 RES 1010 1011 ABh 0 0 Note: (1) DIO = (D6, D4, D2, D0) DO = (D7, D5, D3, D1) (2) Dual Input, DIO = (A22, A20, A18, ………, A6, A4, A2, A0) DO = (A23, A21, A19, …….., A7, A5, A3, A1) (3) ADD= (00h) will output manufacturer’s ID first and ADD=(01h) will output device ID first (April, 2008, Version 0.0) 10 AMIC Technology Corp. A25L016 Series Write Enable (WREN) The Write Enable (WREN) instruction (Figure 4.) sets the Write Enable Latch (WEL) bit. The Write Enable Latch (WEL) bit must be set prior to every Page Program (PP), Sector Erase (SE), Block Erase (BE), Chip Erase (CE) and Write Status Register (WRSR) instruction. The Write Enable (WREN) instruction is entered by driving Chip Select ( S ) Low, sending the instruction code, and then driving Chip Select ( S ) High. Figure 4. Write Enable (WREN) Instruction Sequence S 0 C Instruction DIO High Impedance 1 23 45 6 7 DO Write Disable (WRDI) The Write Disable (WRDI) instruction (Figure 5.) 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 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 Block Erase (BE) instruction completion Chip Erase (CE) instruction completion Figure 5. Write Disable (WRDI) Instruction Sequence S 0 C Instruction DIO High Impedance 1 23 45 6 7 DO (April, 2008, Version 0.0) 11 AMIC Technology Corp. A25L016 Series 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 6. 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 more of the Block Protect (BP2, BP1, BP0) bits is set to 1, the relevant memory area (as defined in Table 1.) becomes protected against Page Program (PP), Sector Erase (SE), and Block Erase (BE) instructions. The Block Protect (BP2, BP1, BP0) bits can be written provided that the Hardware Protected mode has not been set. The Chip Erase (CE) instruction is executed if, and only if, all 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, TB, BP2, BP1, BP0) become read-only bits and the Write Status Register (WRSR) instruction is no longer accepted for execution. Table 4. Status Register Format b7 SRWD b6 0 b5 0 b4 BP2 b3 BP1 b2 BP0 b1 WEL b0 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. Figure 6. Read Status Register (RDSR) Instruction Sequence and Data-Out Sequence S 0 C Instruction DIO Status Register Out DO High Impedance 765 MSB 4 321 0 Status Register Out 76 MSB 5 43 21 0 7 1 234 56 78 9 10 11 12 13 14 15 (April, 2008, Version 0.0) 12 AMIC Technology Corp. A25L016 Series 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 (DIO). The instruction sequence is shown in Figure 7. 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 1. 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. Figure 7. Write Status Register (WRSR) Instruction Sequence S 0 C Instruction Status Register In 7 High Impedance 65 4 321 0 1 234 56 78 9 10 11 12 13 14 15 DIO DO MSB (April, 2008, Version 0.0) 13 AMIC Technology Corp. A25L016 Series Table 5. Protection Modes W Signal SRWD Bit Mode Write Protection of the Status Register Memory Content Protected Area1 Unprotected Area1 1 0 1 0 0 1 Software Protected (SPM) Status Register is Writable (if the WREN instruction has set the WEL bit) The values in the SRWD, TB, BP2, BP1, and BP0 bits can be changed Protected against Page Program, Dual Input Fast Program, Sector Erase, Block Erase, and Chip Erase Ready to accept Page Program, Dual Input Fast Program, Sector Erase, and Block Erase instructions 0 1 Hardware Protected (HPM) Status Register is Hardware write protected The values in the SRWD, TB, BP2, BP1, and BP0 bits cannot be changed Protected against Page Program, Dual Input Fast Program, Sector Erase, Block Erase, and Chip Erase Ready to accept Page Program, Dual Input Fast Program, Sector Erase, and Block Erase instructions Note: 1. As defined by the values in the Block Protect (TB, BP2, BP1, BP0) bits of the Status Register, as shown in Table 1. The protection features of the device are summarized in Table 5. When the Status Register Write Disable (SRWD) bit of the Status Register is 0 (its initial delivery state), it is possible to write to the Status Register provided that the Write Enable Latch (WEL) bit has previously been set by a Write Enable (WREN) instruction, regardless of the whether Write Protect ( W ) is driven High or Low. When the Status Register Write Disable (SRWD) bit of the Status Register is set to 1, two cases need to be considered, depending on the state of Write Protect ( W ): ­ If Write Protect ( W ) is driven High, it is possible to write to the Status Register provided that the Write Enable Latch (WEL) bit has previously been set by a Write Enable (WREN) instruction. ­ If Write Protect (W) is driven Low, it is not possible to write to the Status Register even if the Write Enable Latch (WEL) bit has previously been set by a Write Enable (WREN) instruction. (Attempts to write to the Status Register are rejected, and are not accepted for execution). As a consequence, all the data bytes in the memory area that are software protected (SPM) by the Block Protect (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. (April, 2008, Version 0.0) 14 AMIC Technology Corp. A25L016 Series 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 (DO), 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 8. 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. Figure 8. Read Data Bytes (READ) Instruction Sequence and Data-Out Sequence S 0 C Instruction DIO High Impedance 24-Bit Address 23 22 21 MSB DO 76 MSB 3 2 1 0 Data Out 1 5 4 3 2 1 0 Data Out 2 7 1 234 56 78 9 10 28 29 30 31 32 33 34 35 36 37 38 39 Note:. Address bits A23 to A21 are Don’t Care, for A25L016. (April, 2008, Version 0.0) 15 AMIC Technology Corp. A25L016 Series 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 (DO), 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 9. The first byte addressed can be at any location. The address is automatically incremented to the next higher address after each byte of data is shifted out. The whole memory can, therefore, be read with a single Read Data Bytes 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. Figure 9. Read Data Bytes at Higher Speed (FAST_READ) Instruction Sequence and Data-Out Sequence S 0 C Instruction DIO High Impedance 24-Bit Address 23 22 21 MSB DO 3 2 1 0 1 234 56 78 9 10 28 29 30 31 S 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 C Dummy Byte DIO 76 5 4 3 21 0 Data Out 1 DO 76 MSB 5 4 3 2 1 0 76 MSB Data Out 2 5 4 3 2 1 0 7 MSB Note:. Address bits A23 to A21 are Don’t Care, for A25L016. (April, 2008, Version 0.0) 16 AMIC Technology Corp. A25L016 Series Fast Read Dual Output (3Bh) The Fast Read Dual Output (3Bh) instruction is similar to the Fast Read (0Bh) instruction except the data is output on two pins, DO and DIO, instead of just DO. This allows data to be transferred from the A25L016 at twice the rate of standard SPI devices. Similar to the Fast Read instruction, the Fast Read Dual Output instruction can operate at the highest possible frequency of fC (See AC Characteristics). This is accomplished by adding eight “dummy” clocks after the 24-bit address as shown in figure 10. The dummy clocks allow the device’s internal circuits additional time for setting up the initial address. The input data during the dummy clocks is “don’t care”. However, the DIO pin should be high-impedance prior to the falling edge of the first data out clock. Figure 10. FAST_READ_DUAL_OUTPUT Instruction Sequence and Data-Out Sequence S 0 C Instruction DIO High Impedance 24-Bit Address 23 22 21 MSB DO 3 2 1 0 1 234 56 78 9 10 28 29 30 31 S 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 C Dummy Byte DIO 76 5 4 3 21 0 6 DIO switches from input to output 4 2 0 6 4 2 0 6 4 2 0 6 4 2 0 DO 75 MSB 3 1 7 5 3 1 75 MSB 3 1 7 5 3 1 7 MSB Data Out 1 Data Out 2 Data Out 3 Data Out 4 Note:. Address bits A23 to A21 are Don’t Care, for A25L016. (April, 2008, Version 0.0) 17 AMIC Technology Corp. A25L016 Series Fast Read Dual Input-Output (BBh) The Fast Read Dual Input-Output (BBh) instruction is similar to the Fast_Read (0Bh) instruction except the data is input and output on two pins, DO and DIO, instead of just DO. This allows data to be transferred from the A25L016 at twice the rate of standard SPI devices. Similar to the Fast Read instruction, the Fast Read Dual Output instruction can operate at the highest possible frequency of fC (See AC Characteristics). This is accomplished by adding four “dummy” clocks after the 24-bit address as shown in figure 11. The dummy clocks allow the device’s internal circuits additional time for setting up the initial address. The input data during the dummy clocks is “don’t care”. However, the DIO and DO pins should be high-impedance prior to the falling edge of the first data out clock. Figure 11. FAST_READ_DUAL_INPUT-OUTPUT Instruction Sequence and Data-Out Sequence S 0 C Instruction DIO High Impedance 24-Bit Address 22 20 18 MSB DO 23 21 19 7 5 3 1 6 4 2 0 1 234 56 78 9 10 16 17 18 19 S 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 C Dummy Byte DIO switches from input to output 0 6 4 2 06 4 2 0 6 4 2 0 6 4 2 0 6 4 2 0 DIO 3 2 1 DO 753 MSB Data Out 1 1 75 MSB 3 1 7 5 3 1 75 MSB 3 1 7 5 3 1 7 MSB Data Out 2 Data Out 3 Data Out 4 Data Out 5 Note:. Address bits A23 to A21 are Don’t Care, for A25L016. (April, 2008, Version 0.0) 18 AMIC Technology Corp. A25L016 Series 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 (DIO). 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 12. 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 self-timed Page Program cycle (whose duration is tPP) is initiated. While the Page Program cycle is in progress, the Status Register may be read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is 1 during the self-timed Page Program cycle, and is 0 when it is completed. At some unspecified time before the cycle is completed, the Write Enable Latch (WEL) bit is reset. A Page Program (PP) instruction applied to a page which is protected by the Block Protect (BP2, BP1, BP0) bits (see table 1 and table 2) is not executed. Figure 12. Page Program (PP) Instruction Sequence S 0 C Instruction DIO 24-Bit Address 23 22 21 MSB 3 2 1 0 76 MSB Data Byte 1 5 4 3 2 1 0 1 234 56 78 9 10 28 29 30 31 32 33 34 35 36 37 38 39 2072 2073 2074 2075 2076 2077 2 2078 1 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 C Data Byte 2 DIO 76 MSB 5 4 3 2 1 0 76 MSB Data Byte 3 5 4 3 2 1 0 Data Byte 256 76 MSB 5 4 3 0 Note:. Address bits A23 to A21 are Don’t Care, for A25L016. (April, 2008, Version 0.0) 19 AMIC Technology Corp. 2079 S A25L016 Series 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 on Serial Data Input (DIO). Chip Select ( S ) must be driven Low for the entire duration of the sequence. The instruction sequence is shown in Figure 13. Chip Select ( S ) must be driven High after the eighth bit of the instruction code has been latched in, otherwise the Sector Erase 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 (TB, BP2, BP1, BP0) bits (see table 1 and table 2) is not executed. Figure 13. Sector Erase (SE) Instruction Sequence S 0 C Instruction DIO 24-Bit Address 23 22 21 MSB Note:. Address bits A23 to A21 are Don’t Care, for A25L016. 1 234 56 78 9 10 28 29 30 31 3 2 1 0 (April, 2008, Version 0.0) 20 AMIC Technology Corp. A25L016 Series Block Erase (BE) The Block Erase (BE) instruction sets to 1 (FFh) all bits inside the chosen block. Before it can be accepted, a Write Enable (WREN) instruction must previously have been executed. After the Write Enable (WREN) instruction has been decoded, the device sets the Write Enable Latch (WEL). The Block Erase (BE) instruction is entered by driving Chip Select ( S ) Low, followed by the instruction code on Serial Data Input (DIO). Chip Select ( S ) must be driven Low for the entire duration of the sequence. The instruction sequence is shown in Figure 14. Chip Select ( S ) must be driven High after the eighth bit of the instruction code has been latched in, otherwise the Block Erase instruction is not executed. As soon as Chip Select ( S ) is driven High, the self-timed Block Erase cycle (whose duration is tBE) is initiated. While the Block Erase cycle is in progress, the Status Register may be read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is 1 during the self-timed Block Erase cycle, and is 0 when it is completed. At some unspecified time before the cycle is completed, the Write Enable Latch (WEL) bit is reset. A Block Erase (BE) instruction applied to a page which is protected by the Block Protect (TB, BP2, BP1, BP0) bits (see table 1and table 2) is not executed. Figure 14. Block Erase (BE) Instruction Sequence S 0 C Instruction DIO 24-Bit Address 23 22 21 MSB Note:. Address bits A23 to A21 are Don’t Care, for A25L016. 1 234 56 78 9 10 28 29 30 31 3 2 1 0 (April, 2008, Version 0.0) 21 AMIC Technology Corp. A25L016 Series Chip Erase (CE) The Chip Erase (CE) instruction sets all bits to 1 (FFh). Before it can be accepted, a Write Enable (WREN) instruction must previously have been executed. After the Write Enable (WREN) instruction has been decoded, the device sets the Write Enable Latch (WEL). The Chip Erase (CE) instruction is entered by driving Chip Select ( S ) Low, followed by the instruction code on Serial Data Input (DIO). Chip Select ( S ) must be driven Low for the entire duration of the sequence. The instruction sequence is shown in Figure 15. Chip Select ( S ) must be driven High after the eighth bit of the instruction code has been latched in, otherwise the Block Erase instruction is not executed. As soon as Chip Select ( S ) is driven High, the self-timed Chip Erase cycle (whose duration is tCE) is initiated. While the Chip Erase cycle is in progress, the Status Register may be read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is 1 during the self-timed Chip Erase cycle, and is 0 when it is completed. At some unspecified time before the cycle is completed, the Write Enable Latch (WEL) bit is reset. The Chip Erase (CE) instruction is executed only if all Block Protect (TB, BP2, BP1, BP0) bits are 0. The Chip Erase (CE) instruction is ignored if one, or more, blocks are protected. Figure 15. Chip Erase (CE) Instruction Sequence S 0 C Instruction DIO 1 2 3 45 6 7 Note:. Address bits A23 to A21 are Don’t Care, for A25L016. (April, 2008, Version 0.0) 22 AMIC Technology Corp. A25L016 Series 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 ICC1 to ICC2, as specified in DC Characteristics Table.). Once the device has entered the Deep Power-down 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 Signature of the device to be output on Serial Data Output (DO). The Deep Power-down mode automatically stops at Power-down, and the device always Powers-up in the Standby mode. The Deep Power-down (DP) instruction is entered by driving Chip Select ( S ) Low, followed by the instruction code on Serial Data Input (DIO). 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 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. Figure 16. Deep Power-down (DP) Instruction Sequence S 01 C Instruction DIO Stand-by Mode Deep Power-down Mode 2 3 45 6 7 tDP (April, 2008, Version 0.0) 23 AMIC Technology Corp. A25L016 Series Read Device Identification (RDID) The Read Identification (RDID) instruction allows the 8-bit manufacturer identification code to be read, followed by two bytes of device identification. The manufacturer identification is assigned by JEDEC, and has the value 37h. The device identification is assigned by the device manufacturer, and indicates the memory in the first bytes (30h), and the memory capacity of the device in the second byte (16h for A25L032, 15h for A25L016). Any Read Identification (RDID) instruction while an Erase, or Program cycle is in progress, is not decoded, and has no effect on the cycle that is in progress. The device is first selected by driving Chip Select ( S ) Low. Then, the 8-bit instruction code for the instruction is shifted in. This is followed by the 24-bit device identification, stored in the memory, being shifted out on Serial Data Output (DO), each bit being shifted out during the falling edge of Serial Clock (C). The instruction sequence is shown in Figure 17. The Read Identification (RDID) instruction is terminated by driving Chip Select ( S ) High at any time during data output. When Chip Select ( S ) is driven High, the device is put in the Stand-by Power mode. Once in the Stand-by Power mode, the device waits to be selected, so that it can receive, decode and execute instructions. Table 6. Read Identification (READ_ID) Data-Out Sequence Manufacture Identification Device Identification Manufacture ID 37h Memory Type 30h Memory Capacity 15h Figure 17. Read Identification (RDID) Instruction Sequence and Data-Out Sequence S 01 2 3 4 5 6 7 8 9 10 13 14 15 16 17 18 21 22 23 24 25 26 29 30 31 C Instruction DIO DO High Impedance 23 22 21 18 17 16 15 14 13 10 9 8 7 6 5 2 1 0 Manufacture ID Memory Type Memory Capacity (April, 2008, Version 0.0) 24 AMIC Technology Corp. A25L016 Series Read Electronic Manufacturer ID & Device ID (REMS) The Read Electronic Manufacturer ID & Device ID (REMS) instruction allows the 8-bit manufacturer identification code to be read, followed by one byte of device identification. The manufacturer identification is assigned by JEDEC, and has the value 37h for AMIC. The device identification is assigned by the device manufacturer, and has the value 15h for A25L032, 14h for A25L016. Any Read Electronic Manufacturer ID & Device ID (REMS) instruction while an Erase, or Program cycle is in progress, is not decoded, and has no effect on the cycle that is in progress. The device is first selected by driving Chip Select ( S ) Low. The 8-bit instruction code is followd by 2 dummy bytes and one byte address(A7~A0), each bit being latched-in on Serial Data Input (DIO) during the rising edge of Serial Clock (C). If the one-byte address is set to 01h, then the device ID be read first and then followed by the Manufacturer ID. the other hand, if the one-byte address is set to 00h, then Manufacturer ID will be read first and then followed by device ID. will On the the The instruction sequence is shown in Figure 18. The Read Electronic Manufacturer ID & Device ID (REMS) instruction is terminated by driving Chip Select ( S ) High at any time during data output. When Chip Select ( S ) is driven High, the device is put in the Stand-by Power mode. Once in the Stand-by Power mode, the device waits to be selected, so that it can receive, decode and execute instructions. Table 7. Read Electronic Manufacturer ID & Device ID (REMS) Data-Out Sequence Manufacture Identification Device Identification 37h 14h Figure 18. Read Electronic Manufacturer ID & Device ID (REMS) Instruction Sequence and Data-Out Sequence S 0 1 2 3 4 5 6 7 8 9 10 C Instruction DIO High Impedance 2 Dummy Bytes 15 14 13 MSB DO 3210 20 21 22 23 S 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 C ADD(1) DIO 76543210 Manufacturer ID DO Device ID 7654321076543210 MSB MSB MSB Notes: (1) ADD=00h will output the manufacturer ID first and ADD=01h will output device ID first (April, 2008, Version 0.0) 25 AMIC Technology Corp. A25L016 Series Release from Deep Power-down Electronic Signature (RES) and Read edge of Serial Clock (C). Then, the 8-bit Electronic Signature, stored in the memory, is shifted out on Serial Data Output (DO), each bit being shifted out during the falling edge of Serial Clock (C). The instruction sequence is shown in Figure 19. 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 AC Characteristics Table . Once in the Stand-by Power mode, the device waits to be selected, so that it can receive, decode and execute instructions. Once the device has entered the Deep Power-down 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 (DO), the 8-bit Electronic Signature, whose value for the A25L032 is 15h, and for A25L016 is 14h. 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 8-bit 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. 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 (DIO) during the rising Figure 19. Release from Deep Power-down and Read Electronic Signature (RES) Instruction Sequence and Data-Out Sequence S 0 C Instruction DIO High Impedance 3 Dummy Bytes 23 22 21 MSB DO 76 MSB Deep Power-down Mode Stand-by Mode 5 4 3 2 1 0 3 2 1 0 tRES2 1 234 56 78 9 10 28 29 30 31 32 33 34 35 36 37 38 Note: The value of the 8-bit Electronic Signature is 14h. (April, 2008, Version 0.0) 26 AMIC Technology Corp. A25L016 Series Figure 20. Release from Deep Power-down (RES) Instruction Sequence S 01 2 3 45 6 7 tRES1 C Instruction DIO High Impedance DO Deep Power-down Mode Stand-by Mode 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 20.), 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 the device was previously in the Deep Power-down mode, though, the transition to the Stand-by Power mode is delayed by tRES1, and Chip Select ( S ) must remain High for at least tRES1 (max), as specified in AC Characteristics Table. Once in the Stand-by Power mode, the device waits to be selected, so that it can receive, decode and execute instructions. (April, 2008, Version 0.0) 27 AMIC Technology Corp. A25L016 Series 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 VCC reaches the correct value: ­ ­ ­ tPUW after VCC passed the VWI threshold - tVSL afterVCC passed the VCC(min) level These values are specified in Table 8. 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: 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 VCC is less than the POR threshold value, VWI – 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), Block Erase (BE), Chip Erase (CE) and Write Status Register (WRSR) instructions until a time delay of tPUW has elapsed after the moment that VCC 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: 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 stabilize 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 21. Power-up Timing VCC VCC(max) VCC(min) tPU Full Device Access time (April, 2008, Version 0.0) 28 AMIC Technology Corp. A25L016 Series Table 8. Power-Up Timing Symbol Parameter Min. Max. Unit VCC(min) tPU VCC (minimum) VCC (min) to device operation 2.7 5 V ms Note: 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 FFh). The Status Register contains 00h (all Status Register bits are 0). (April, 2008, Version 0.0) 29 AMIC Technology Corp. A25L016 Series Absolute Maximum Ratings* Storage Temperature (TSTG) . . . . . . . . . . -65°C to + 150°C Lead Temperature during Soldering (Note 1) D.C. Voltage on Any Pin to Ground Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.6V to VCC+0.6V Transient Voltage (