K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY Document Title 16M x 8 Bit NAND Flash Memory Revision History Revision No. History Draft Date Remark Advance 0.0 Initial issue. May 28'th 2001 0.1 K9F2808U0B(3.3V device)'s qualification is finished Jun. 30th 2001 0.2 K9F2808Q0B (1.8V device) - Changed typical read operation current (Icc1) from 8mA to 5mA - Changed typical program operation current (Icc2) from 8mA to 5mA - Changed typical erase operation current (Icc3) from 8mA to 5mA - Changed typical program time(tPROG) from 200us to 300us - Changed ALE to RE Delay (ID read, tAR1) from 100ns to 20ns - Changed CLE hold time(tCLH) from 10ns to 15ns - Changed CE hold time(tCH) from 10ns to 15ns - Changed ALE hold time(tALH) from 10ns to 15ns - Changed Data hold time(tDH) from 10ns to 15ns - Changed CE Access time(tCEA) from 45ns to 60ns - Changed Read cycle time(tRC) from 50ns to 70ns - Changed Write Cycle time(tWC) from 50ns to 70ns - Changed RE Access time(tREA) from 35ns to 40ns - Changed RE High Hold time(tREH) from 15ns to 20ns - Changed WE High Hold time(tWH) from 15ns to 20ns 0.3 1. Device Code is changed - TBGA package information : 'B' --> 'D' ex) K9F2808Q0B-BCB0 ,BIB0 --> K9F2808Q0B-DCB0,DIB0 K9F2808U0B-BCB0 ,BIB0 --> K9F2808Q0B-DCB0,DIB0 2. V IH ,VIL of K9F2808Q0B(1.8 device) is changed Jul. 30th 2001 K9F2808Q0B : Preliminary Aug. 23th 2001 (before revision) Input High Voltage V IH Input Low Voltage, All inputs V IL I/O pins VccQ-0.4 VccQ Except I/O pins V CC-0.4 - VCC - 0 - 0.4 (after revision) I/O pins Input High Voltage Input Low Voltage, All inputs VccQ +0.3 VccQ-0.4 V IH V IL Except I/O pins V CC-0.4 - VCC +0.3 - -0.3 - 0.4 Note : For more detailed features and specifications including FAQ, please refer to Samsung's Flash web site. http://www.intl.samsungsemi.com/Memory/Flash/datasheets.html The attached datasheets are prepared and approved by SAMSUNG Electronics. SAMSUNG Electronics CO., LTD. reserve the right to change the specifications. SAMSUNG Electronics will evaluate and reply to your requests and questions about device. If you have any questions, please contact the SAMSUNG branch office near you. 1 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY Revision History Revision No. History 0.4 1. IOL (R/B) of 1.8V device is changed. Draft Date Remark Nov 5th 2001 Preliminary -min. Value: 7mA -->3mA -typ. Value: 8mA -->4mA 2. AC parameter is changed. tRP(min.) : 30ns --> 25ns 0.5 1. Parameters are changed in 1.8V part(K9F2808Q0B) . Feb 15th 2002 - tCH is changed from 15ns to 20ns - tCLH is changed from 15ns to 20ns - tALH is changed from 15ns to 20ns - tDH is changed from 15ns to 20ns 0.6 1. Parameters are changed in 1.8V part(K9F2808Q0B) . May 3rd 2002 - tRP is changed from 25ns to 35ns - tWB is changed from 100ns to 150ns - tREA is changed from 40ns to 45ns Note : For more detailed features and specifications including FAQ, please refer to Samsung's Flash web site. http://www.intl.samsungsemi.com/Memory/Flash/datasheets.html The attached datasheets are prepared and approved by SAMSUNG Electronics. SAMSUNG Electronics CO., LTD. reserve the right to change the specifications. SAMSUNG Electronics will evaluate and reply to your requests and questions about device. If you have any questions, please contact the SAMSUNG branch office near you. 2 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY 16M x 8 Bit Bit NAND Flash Memory PRODUCT LIST Part Number Vcc Range K9F2808Q0B-D 1.7 ~ 1.9V Organization TBGA K9F2808U0B-Y K9F2808U0B-D PKG Type X8 2.7 ~ 3.6V TSOP1 TBGA K9F2808U0B-V WSOP1 FEATURES * Voltage Supply - K9F2808Q0B : 1.7~1.9V - K9F2808U0B : 2.7 ~ 3.6 V * Organization - Memory Cell Array : (16M + 512K)bit x 8bit - Data Register : (512 + 16)bit x8bit * Automatic Program and Erase - Page Program : (512 + 16)Byte - Block Erase : (16K + 512)Byte * 528-Byte Page Read Operation - Random Access : 10s(Max.) - Serial Page Access - K9F2808Q0B : 70ns - K9F2808U0B : 50ns * Fast Write Cycle Time - Program Time - K9F2808Q0B : 300 s(Typ.) - K9F2808U0B : 200s(Typ.) - Block Erase Time : 2ms(Typ.) * Command/Address/Data Multiplexed I/O Port * Hardware Data Protection - Program/Erase Lockout During Power Transitions * Reliable CMOS Floating-Gate Technology - Endurance : 100K Program/Erase Cycles - Data Retention : 10 Years * Command Register Operation * Package - K9F2808U0B-YCB0/YIB0 : 48 - Pin TSOP I (12 x 20 / 0.5 mm pitch) - K9F2808X0B-DCB 0/ DIB0 63- Ball TBGA ( 9 x 11 /0.8mm pitch , Width 1.0 mm) - K9F2808U0B-VCB0/VIB0 48 - Pin WSOP I (12X17X0.7mm) * K9F2808U0B-V(WSOPI ) is the same device as K9F2808U0B-Y(TSOP1) except package type. GENERAL DESCRIPTION The K9F2808X0B is a 16M(16,777,216)x8bit NAND Flash Memory with a spare 512K(524,288)x8bit. The device is offered in 1.8V or 3.3V Vcc. Its NAND cell provides the most cost-effective solution for the solid state mass storage market. A program operation programs the 528-byte page in typical 200s and an erase operation can be performed in typical 2ms on a 16K-byte block. Data in a page can be read out at 70ns/50ns(K9F2808Q0B:70ns, K9F2808U0B:50ns) cycle time per byte. The I/O pins serve as the ports for address and data input/output as well as command input. The on-chip write control automates all program and erase functions including pulse repetition, where required, and internal verification and margining of data. Even write-intensive systems can take advantage of the K9F2808X0B's extended reliability of 100K program/erase cycles by providing ECC(Error Correcting Code) with real time mapping-out algorithm. The K9F2808X0B is suitable for use in data memory of mobile communication system to reduce not only mount area but also power consumption. 3 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY PIN CONFIGURATION (TSOP1) K9F2808U0B-YCB0/YIB0 N.C N.C N.C N.C N.C GND R/B RE CE N.C N.C Vcc Vss N.C N.C CLE ALE WE WP N.C N.C N.C N.C N.C N.C N.C N.C N.C I/O7 I/O6 I/O5 I/O4 N.C N.C N.C Vcc Vss N.C N.C N.C I/O3 I/O2 I/O1 I/O0 N.C N.C N.C N.C 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 PACKAGE DIMENSIONS 48-PIN LEAD PLASTIC THIN SMALL OUT-LINE PACKAGE TYPE(I) 48 - TSOP1 - 1220F 0.10 #48 #24 #25 0.50 0.0 197 12 .40 MAX 0.488 ( 0 .25 ) 0.010 #1 12.00 0.472 +0 .0 03 0 .00 8- 0.0 0 1 0.20 -0 .0 3 +0 .07 20.00 0.20 0.787 0.008 0.004 MAX Unit :mm/Inch +0 .07 5 0~8AE 0.45~0.75 0.018~0.030 +0 .00 3 0.005-0 .0 01 18.40 0.10 0.724 0.004 0.1 25 0 .03 5 0 .25 0.010 TYP 1.00 0.05 0.039 0.002 ( 0.50 ) 0.020 4 1.20 0.047 MAX 0.05 MIN 0.002 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY PIN CONFIGURATION (TBGA) K9F2808X0B-DCB0/DIB0 DNU DNU DNU DNU DNU DNU DNU /WP ALE NC /CE /WE R/B NC /RE CLE NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC I/O0 NC NC I/O1 NC Vss I/O2 I/O3 I/O4 NC NC VccQ I/O5 I/O6 Vcc I/O7 Vss DNU DNU DNU DNU DNU DNU DNU DNU (Top View) PACKAGE DIMENSIONS 63-Ball TBGA (measured in millimeters) Top View Bottom View 9.00 0.10 0.80 x9= 7.20 0.80 x5= 4.00 9.00 0.10 6 5 0.80 4 3 2 B 1 0.80 (Datum A) A #A1 A D 2.80 E F G H 63-0.45 0.05 2.00 0.32 0.05 Side View 9.00 0.10 0.08MAX 5 0.45 0.05 0.90 0.10 0.20 M A B 11.00 0.10 C 0.80 x7= 5.60 11.00 0.10 (Datum B) 0.80 x11= 8.80 B K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY PIN CONFIGURATION (WSOP1) K9F2808U0B-VCB0/VIB0 N.C N.C DNU N.C N.C N.C R/B RE CE DNU N.C Vcc Vss N.C DNU CLE ALE WE WP N.C N.C DNU N.C N.C 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 N.C N.C DNU N.C I/O7 I/O6 I/O5 I/O4 N.C DNU N.C Vcc Vss N.C DNU N.C I/O3 I/O2 I/O1 I/O0 N.C DNU N.C N.C PACKAGE DIMENSIONS 48-PIN LEAD PLASTIC VERY VERY THIN SMALL OUT-LINE PACKAGE TYPE (I) 48 - WSOP1 - 1217F Unit :mm 0.70 MAX 0.58 0.04 15.40 0.10 #48 #24 #25 +0 .0 7 - 0.0 3 0.16 +0.0 7 -0 .03 #1 0.5 0TY P (0.50 0.0 6) 0 .20 1 2.0 00 .1 0 ~8 0 75 0.10 +0.0 -0 .03 5 (0.1Min) 0.45~0.75 17.00 0.20 6 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY PIN DESCRIPTION Pin Name Pin Function I/O0 ~ I/O7 DATA INPUTS/OUTPUTS The I/O pins are used to input command, address and data, and to output data during read operations. The I/O pins float to high-z when the chip is deselected or when the outputs are disabled. CLE COMMAND LATCH ENABLE The CLE input controls the activating path for commands sent to the command register. When active high, commands are latched into the command register through the I/O ports on the rising edge of the WE signal. ALE ADDRESS LATCH ENABLE The ALE input controls the activating path for address to the internal address registers. Addresses are latched on the rising edge of WE with ALE high. CE CHIP ENABLE The CE input is the device selection control. When the device is in the Busy state, CE high is ignored, and the device does not return to standby mode in program or erase opertion. Regarding CE control during read operation, refer to 'Page read' section of Device operation. RE READ ENABLE The RE input is the serial data-out control, and when active drives the data onto the I/O bus. Data is valid tREA after the falling edge of RE which also increments the internal column address counter by one. WE WRITE ENABLE The W E input controls writes to the I/O port. Commands, address and data are latched on the rising edge of the WE pulse. WP WRITE PROTECT The WP pin provides inadvertent write/erase protection during power transitions. The internal high voltage generator is reset when the WP pin is active low. R/B READY/BUSY OUTPUT The R/B output indicates the status of the device operation. When low, it indicates that a program, erase or random read operation is in process and returns to high state upon completion. It is an open drain output and does not float to high-z condition when the chip is deselected or when outputs are disabled. VccQ OUTPUT BUFFER POWER V CCQ is the power supply for Output Buffer. VccQ is internally connected to Vcc, thus should be biased to Vcc. Vcc POWER V CC is the power supply for device. Vss GROUND N.C NO CONNECTION Lead is not internally connected. GND GND INPUT FOR ENABLING SPARE AREA To do sequential read mode including spare area , connect this input pin to Vss or set to static low state or to do sequential read mode excluding spare area , connect this input pin to Vcc or set to static high state. DNU DO NOT USE Leave it disconnected. NOTE : Connect all VCC and V SS pins of each device to common power supply outputs. 7 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY Figure 1. FUNCTIONAL BLOCK DIAGRAM V CC V SS A9 - A 23 X-Buffers Latches & Decoders A0 - A7 Y-Buffers Latches & Decoders 128M + 4M Bit NAND Flash ARRAY (512 + 16)Byte x 32768 Page Register & S/A A8 Y-Gating Command Command Register Vcc/V CCQ V SS I/O Buffers & Latches CE RE WE Control Logic & High Voltage Generator Output Driver Global Buffers I/0 0 I/0 7 CLE ALE WP Figure 2. ARRAY ORGANIZATION 1 Block =32 Pages = (16K + 512) Byte 32K Pages (=1,024 Blocks) 1st half Page Register 2nd half Page Register (=256 Bytes) (=256 Bytes) 1 Page = 528 Byte 1 Block = 528 Bytes x 32 Pages = (16K + 512) Byte 1 Device = 528Byte x 32Pages x 1024 Blocks = 132 Mbits 8 bit 512B Byte 16 Byte I/O 0 ~ I/O 7 Page Register 512 Byte 16 Byte I/O 0 I/O 1 I/O 2 I/O 3 I/O 4 I/O 5 I/O 6 I/O 7 A0 A1 A2 A3 A4 A5 A6 A7 2nd Cycle A9 A 10 A 11 A 12 A 13 A 14 A 15 A 16 3rd Cycle A 17 A 18 A 19 A 20 A 21 A 22 A 23 *L 1st Cycle NOTE : Column Address : Starting Address of the Register. 00h Command(Read) : Defines the starting address of the 1st half of the register. 01h Command(Read) : Defines the starting address of the 2nd half of the register. * A 8 is set to "Low" or "High" by the 00h or 01h Command. * L must be set to "Low". * The device ignores any additional input of address cycles than reguired. 8 Column Address Row Address (Page Address) K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY PRODUCT INTRODUCTION The K9F2808X0B is a 132Mbit(138,412,032 bit) memory organized as 32,768 rows(pages) by 528 columns. Spare 16 columns are located in 512 to 527 column address. A 528-byte data register is connected to memory cell arrays accommodating data transfer between the I/O buffers and memory during page read and page program operations. The memory array is made up of 16 cells that are serially connected like NAND structure. Each of the 16 cells resides in a different page. A block consists of the 32 pages formed by one NAND structures, totaling 8448 NAND structures of 16 cells. The array organization is shown in Figure 2. Program and read operations are executed on a page basis, while erase operation is executed on a block basis. The memory array consists of 1024 blocks, and a block is separately erasable by 16K-byte unit. It indicates that the bit by bit erase operation is prohibited on the K9F2808X0B. The K9F2808X0B has addresses multiplexed with 8 I/O s. This scheme dramatically reduces pin counts and allows systems upgrades to future densities by maintaining consistency in system board design. Command, address and data are all written through I/O s by bringing WE to low while CE is low. Data is latched on the rising edge of WE. Command Latch Enable(CLE) and Address Latch Enable(ALE) are used to multiplex command and address respectively, via the I/O pins. All commands require one bus cycle except Page Program command and Block Erase command which require two cycles: one cycle for setup and another for execution. The 16M byte physical space requires 24 addresses, thereby requiring three cycles for byte-level addressing: column address, low row address and high row address, in that order. Page Read and Page Program need the same three address cycles following required command input. In Block Erase operation, however, only two row address cycles are used. Device operations are selected by writing specific commands into command register. Table 1 defines the specific commands of the K9F2808X0B. Table 1. COMMAND SETS 1st. Cycle 2nd. Cycle Read 1 Function 00h/01h (1) - Read 2 50h - Read ID 90h - Reset FFh - Page Program 80h 10h Block Erase 60h D0h Read Status 70h - Acceptable Command during Busy NOTE : 1. The 00h command defines starting address of the 1st half of registers. The 01h command defines starting address of the 2nd half of registers. After data access on 2nd half of register by the 01h command, start pointer is automatically moved to 1st half register(00h) on the next cycle. Caution : Any undefined command inputs are prohibited except for above command set of Table 1. 9 O O K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 FLASH MEMORY ABSOLUTE MAXIMUM RATINGS Parameter K9F2808X0B-YCB0,DCB0 Unit K9F2808Q0B(1.8V) K9F2808U0B(3.3V) V IN/OUT -0.6 to + 2.45 -0.6 to + 4.6 V V CC -0.2 to + 2.45 -0.6 to + 4.6 V V CCQ -0.2 to + 2.45 -0.6 to + 4.6 V Voltage on any pin relative to V SS Temperature Under Bias Rating Symbol -10 to + 125 TBIAS K9F2808X0B-YIB0,DIB 0 C -40 to + 125 Storage Temperature TSTG C -65 to + 150 NOTE: 1. Minimum DC voltage is -0.6V on input/output pins and -0.2V on Vcc and VccQ pins. During transitions, this level may undershoot to -2.0V for periods <20ns. Maximum DC voltage on input/output pins is V CCQ +0.3V which, during transitions, may overshoot to VC C +2.0V for periods <20ns. 2. Permanent device damage may occur if ABSOLUTE MAXIMUM RATINGS are exceeded. Functional operation should be restricted to the conditions as detailed in the operational sections of this data sheet. Exposure to absolute maximum rating conditions for extended periods may affect reliability. RECOMMENDED OPERATING CONDITIONS (Voltage reference to GND, K9F2808X0B-YCB0,DCB 0:TA=0 to 70C, K9F2808X0B-YIB0,DIB0:T A=-40 to 85C) Parameter K9F2808Q0B(1.8V) Symbol K9F2808U0B(3.3V) Unit Min Typ. Max Min Typ. Max Supply Voltage V CC 1.7 1.8 1.9 2.7 3.3 3.6 V Supply Voltage V CCQ 1.7 1.8 1.9 2.7 3.3 3.6 V Supply Voltage V SS 0 0 0 0 0 0 V DC AND OPERATING CHARACTERISTICS (Recommended operating conditions otherwise noted.) K9F2808Q0B(1.8V) Parameter Symbol Test Conditions CE=VIL, IOUT=0mA K9F2808Q0B: tRC=70ns K9F2808U0B: tRC=50ns K9F2808U0B(3.3V) Min Typ Max Min Typ Max - 5 15 - 10 20 Operat- Sequential Read ing Current Program ICC1 ICC2 - - 5 15 - 10 20 Erase ICC3 - - 5 15 - 10 20 Stand-by Current(TTL) ISB1 CE=VIH, WP =0V/VCC - - 1 - - 1 Stand-by Current(CMOS) ISB2 CE=VCC-0.2, WP =0V/V CC - 10 50 - 10 50 Input Leakage Current ILI V IN=0 to Vcc(max) - - 10 - - 10 Output Leakage Current ILO V OUT=0 to Vcc(max) - - 10 - - 10 VccQ+0 .3 2.0 - V CCQ+0.3 Input High Voltage Input Low Voltage, All inputs Output High Voltage Level Output Low Voltage Level Output Low Current(R/B) I/O pins VccQ-0.4 Except I/O pins V CC-0.4 - VCC +0.3 2.0 - V CC+0.3 -0.3 - 0.4 -0.3 - 0.8 V CCQ-0.1 - - 2.4 - - - - 0.1 - - 0.4 3 4 - 8 10 - V IH V IL V OH V OL K9F2808Q0B :I OH=-100 A K9F2808U0B :I OH=-400A K9F2808Q0B :I OL=100uA K9F2808U0B :I OL =2.1mA IOL K9F2808Q0B :V OL =0.1V (R/B) K9F2808U0B :V OL =0.4V 10 Unit mA A V mA K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY VALID BLOCK Parameter Valid Block Number Symbol Min Typ. Max Unit NVB 1004 - 1024 Blocks NOTE: 1. The K9F2808X0B may include invalid blocks when first shipped. Additional invalid blocks may develop while being used. The number of valid blocks is presented with both cases of invalid blocks considered. Invalid blocks are defined as blocks that contain one or more bad bits . Do not erase or program factory-marked bad blocks. Refer to the attached technical notes for a appropriate management of invalid blocks. 2. The 1st block, which is placed on 00h block address, is fully guaranteed to be a valid block, does not require Error Correcti on. AC TEST CONDITION (K9F2808X0B-YCB0, DCB0 :TA=0 to 70C, K9F2808X0B-YIB0,DIB0:TA=-40 to 85C K9F2808Q0B : Vcc=1.7V~1.9V , K9F2808U0B : Vcc=2.7V~3.6V unless otherwise noted) Parameter K9F2808Q0B K9F2808U0B 0V to VccQ 0.4V to 2.4V Input Pulse Levels Input Rise and Fall Times 5ns 5ns VccQ/2 1.5V K9F2808Q0B:Output Load (VccQ:1.8V +/-10%) K9F2808U0B:Output Load (VccQ:3.0V +/-10%) 1 TTL GATE and CL=30pF 1 TTL GATE and CL=50pF K9F2808U0B:Output Load (VccQ:3.3V +/-10%) - 1 TTL GATE and CL=100pF Input and Output Timing Levels CAPACITANCE( TA=25C, VCC =1.8V/3.3V, f=1.0MHz) Symbol Test Condition Min Max Unit Input/Output Capacitance Item C I/O V IL =0V - 10 pF Input Capacitance C IN V IN=0V - 10 pF NOTE : Capacitance is periodically sampled and not 100% tested. MODE SELECTION CLE ALE CE H L L H H RE WP L H X L H X L L H H L H L H H L L L H H Data Input L L L H X Data Output L L L H H X During Read(Busy) on K9F2808U0B_Y or K9F2808U0B_V X X X X H X During Read(Busy) on the devices except K9F2808U0B_Y and K9F2808U0B_V X X X X X H During Program(Busy) X X X X X H During Erase(Busy) X X X L Write Protect X X X (1) X H WE X X Mode Read Mode Command Input Address Input(3clock) Write Mode Command Input Address Input(3clock) CC(2) Stand-by Symbol Min Typ Max Unit - K9F2808Q0B:3 00 K9F2808U0B:200 500 s - - 2 cycles - - 3 cycles - 2 3 ms 0V/V NOTE : 1. X can be VIL or V IH. 2. WP should be biased to CMOS high or CMOS low for standby. Program/Erase Characteristics Parameter Program Time Number of Partial Program Cycles in the Same Page Block Erase Time tPROG Main Array Nop Spare Array tBERS 11 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY AC Timing Characteristics for Command / Address / Data Input K9F2808Q0B Parameter Symbol K9F2808U0B Min Max Min Max Unit CLE Set-up Time tCLS 0 - 0 - ns CLE Hold Time tCLH 20 - 10 - ns CE Setup Time tCS 0 - 0 - ns CE Hold Time tCH 20 - 10 - ns WE Pulse Width tWP 25 (1) - 25 - ns ALE Setup Time tALS 0 - 0 - ns ALE Hold Time tALH 20 - 10 - ns Data Setup Time tDS 20 - 20 - ns Data Hold Time tDH 20 - 10 - ns Write Cycle Time tWC 70 - 50 - ns WE High Hold Time tWH 20 - 15 - ns NOTE : 1. If tCS is set less than 10ns, tWP must be minimum 35ns, otherwise, tWP may be minimum 25ns. AC Characteristics for Operation K9F2808Q0B Parameter Symbol Min Max K9F2808U0B Min Max Unit tR - 10 - 10 s ALE to RE Delay( ID read ) tAR1 20 - 20 - ns ALE to RE Delay(Read cycle) tAR2 50 - 50 - ns CLE to RE Delay tCLR 50 - 50 - ns Ready to RE Low tRR 20 - 20 - ns RE Pulse Width tRP 35 - 25 - ns WE High to Busy tWB - 150 - 100 ns Read Cycle Time tRC 70 - 50 - ns CE Access Time tCEA - 60 - 45 ns RE Access Time tREA - 45 - 35 ns RE High to Output Hi-Z tRHZ 15 30 15 30 ns CE High to Output Hi-Z tCHZ - 20 - 20 ns RE High Hold Time tREH 20 - 15 - ns tIR 0 - 0 - ns WE High to RE Low tWHR 60 - 60 - ns Device Resetting Time (Read/Program/Erase) tRST - 5/10/500(1) - 5/10/500 (1) s tRB - 100 - 100 ns - 50 +tr(R/B) (3) - 50 +tr(R/B) (3) ns 100 - 100 - ns Data Transfer from Cell to Register Output Hi-Z to RE Low Last RE High to Busy (at sequential read) K9F2808U0B-Y only CE High to Ready(in case of interception by CE at read) CE High Hold Time(at the last serial read) (2) tCRY tCEH NOTE : 1. If reset command(FFh) is written at Ready state, the device goes into Busy for maximum 5us. 2. To break the sequential read cycle, CE must be held high for longer time than tCEH. 3. The time to Ready depends on the value of the pull-up resistor tied R/B pin. 12 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY NAND Flash Technical Notes Invalid Block(s) Invalid blocks are defined as blocks that contain one or more invalid bits whose reliability is not guaranteed by Samsung. The information regarding invalid block(s) is so called as the invalid block information. Devices ,regardless of having invalid block(s), have the same quality level because all valid blocks have same AC and DC characteristics. An invalid block(s) does not affect the performance of valid block(s) because it's bit line and common source line is isolated by a select transistor. The system design must be able to mask out invalid block(s) via address mapping. The 1st block, which is placed on 00h block address, is fully guaranteed to be a valid block, does not require Error Correction. Identifying Invalid Block(s) All device locations are erased(FFh) except locations where the invalid block(s) information is written prior to shipping. The invalid block(s) status is defined by the 6th byte in the spare area. Samsung makes sure that either 1st or 2nd page of every invalid block has non-FFh data at the column address of 517. Since invalid block information is also erasable in most cases, it is impossible to recover the information once it was erased. Therefore, system must be able to recognize the invalid block(s) based on the original invalid block information and create invalid block table via the following suggested flow chart(Figure 3). Any intentional erasure of the original invalid block information is prohibited. Start Set Block Address = 0 Increment Block Address Create (or update) Invalid Block(s) Table No * Check "FFh" at the column address 517 of the 1st and 2nd page in the block Check "FFh" ? Yes No Last Block ? Yes End Figure 3. Flow chart to create invalid block table. 13 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY NAND Flash Technical Notes (Continued) Error in write or read operation Within its life time, the additional invalid blocks may develop with NAND Flash memory. Refer to the qualification report for actual data. The following possible failure modes should be considered to implement a highly reliable system. In the case of status read failure after erase or program, block replacement should be done. Because program status fail during a page program does not affect the data of the other pages in the same block, block replacement can be executed with a page-sized buffer by finding an erased empty block and reprogramming the current target data and copying the rest of the replaced block. To improve the efficiency of memory space, we recommend using ECC without any block replacement in read or verification failure due to single bit error case. Th e said additional block failure rate does not include those reclaimed blocks. Failure Mode Write Read ECC Detection and Countermeasure sequence Erase Failure Status Read after Erase --> Block Replacement Program Failure Status Read after Program --> Block Replacement Read back ( Verify after Program) --> Block Replacement or ECC Correction Single Bit Failure Verify ECC -> ECC Correction : Error Correcting Code --> Hamming Code etc. Example) 1bit correction & 2bit detection Program Flow Chart If ECC is used, this verification operation is not needed. Start Write 00h Write 80h Write Address Write Address Write Data Wait for tR Time Write 10h Verify Data Read Status Register No * Program Error Yes Program Completed I/O 6 = 1 ? or R/B = 1 ? * Program Error Yes No No * I/O 0 = 0 ? Yes 14 : If program operation results in an error, map out the block including the page in error and copy the target data to another block. K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 FLASH MEMORY NAND Flash Technical Notes (Continued) Erase Flow Chart Read Flow Chart Start Start Write 60h Write 00h Write Block Address Write Address Write D0h Read Data Read Status Register ECC Generation No I/O 6 = 1 ? or R/B = 1 ? Reclaim the Error No Verify ECC Yes Yes * Erase Error No Page Read Completed I/O 0 = 0 ? Yes Erase Completed * : If erase operation results in an error, map out the failing block and replace it with another block. Block Replacement 1st (n-1)th { nth Block A 2 an error occurs. (page) 1st (n-1)th Buffer memory of the controller. { Block B 1 nth (page) * Step1 When an error happens in the nth page of the Block 'A' during erase or program operation. * Step2 Copy the nth page data of the Block 'A' in the buffer memory to the nth page of another free block. (Block 'B') * Step3 Then, copy the data in the 1st ~ (n-1)th page to the same location of the Block 'B'. * Step4 Do not further erase Block 'A' by creating an 'invalid Block' table or other appropriate scheme. 15 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY Pointer Operation of K9F2808X0B Samsung NAND Flash has three address pointer commands as a substitute for the two most significant column addresses. '00h' command sets the pointer to 'A' area(0~255byte), '01h' command sets the pointer to 'B' area(256~511byte), and '50h' command sets the pointer to 'C' area(512~527byte). With these commands, starting column address can be set to somewhere of a whole page(0~527byte). '00h' or '50h' is sustained until another address pointer command is entered. But, '01h' command is effective only for one time operation. After any operation of Read, Program, Erase, Reset, Power_Up following '01h' command, the address pointer returns to 'A' area by itself. To program data starting from 'A' or 'C' area, '00h' or '50h' command must be entered before '80h' command is written. A complete read operation prior to '80h' command is not necessary. To program data starting from 'B' area, '01h' command must be entered right before '80h' command is written. Table 2. Destination of the pointer Command Pointer position Area 00h 01h 50h 0 ~ 255 byte 256 ~ 511 byte 512 ~ 527 byte 1st half array(A) 2nd half array(B) spare array(C) "A" area (00h plane) "B" area (01h plane) "C" area (50h plane) 256 Byte 256 Byte 16 Byte "A" "B" "C" Internal Page Register Pointer select commnad (00h, 01h, 50h) Pointer Figure 4. Block Diagram of Pointer Operation (1) Command input sequence for programming 'A' area The address pointer is set to 'A' area(0~255), and sustained Address / Data input 00h 80h Address / Data input 10h 00h 'A','B','C' area can be programmed. It depends on how many data are inputted. 80h 10h '00h' command can be omitted. (2) Command input sequence for programming 'B' area The address pointer is set to 'B' area(256~512), and will be reset to 'A' area after every program operation is executed. Address / Data input 01h 80h Address / Data input 10h 01h 'B', 'C' area can be programmed. It depends on how many data are inputted. 80h 10h '01h' command must be rewritten before every program operation (3) Command input sequence for programming 'C' area The address pointer is set to 'C' area(512~527), and sustained Address / Data input 50h 80h Address / Data input 10h 50h Only 'C' area can be programmed. 80h '50h' command can be omitted. 16 10h K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY System Interface Using CE don't-care. For an easier system interface, CE may be inactive during data-loading or sequential data-reading as shown below. The internal 528byte page registers are utilized as seperate buffers for this operation and the system design gets more flexible. In addition, for voice or audio applications which use slow cycle time on the order of u-seconds, de-activating CE during the data-loading and reading would provide significant saving in power consumption. Figure 5. Program Operation with CE don't-care. CLE CE don't-care CE WE ALE I/O0~7 80h Start Add.(3Cycle) t CS Data Input tCH Data Input 10h tCEA CE CE tREA RE tWP WE I/O0~7 out Figure 6. Read Operation with CE don't-care. On K9F2808U0B_Y or K9F2808U0B_V CE must be held low during tR CLE CE don't-care CE RE ALE tR R/B WE I/O0~7 00h Data Output(sequential) Start Add.(3Cycle) 17 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY * Command Latch Cycle CLE tCLS tCLH tCS t CH CE tWP WE t ALH tALS ALE t DH t DS Command I/O0 ~7 * Address Latch Cycle tCLS CLE t CS t WC tWC CE tWP t WP tWP WE tWH tALH tALS tALS t WH tALH tALS tALH ALE t DS I/O 0~7 tDH tDS A0~A7 t DH A9~A16 18 tDS tDH A17~A23 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY * Input Data Latch Cycle t CLH CLE tCH CE tWC t ALS tWP tWP ALE tWP WE I/O 0~7 tWH t DH DIN 0 t DS tDH DIN 1 t DS tDS tDH DIN 511 * Serial Access Cycle after Read(CLE=L, WE=H, ALE=L) t RC CE tCHZ tOH tREH tREA t REA tRP RE t REA I/O0~7 Dout Dout t RHZ t RHZ t OH Dout tRR R/B NOTES : Transition is measured 200mV from steady state voltage with load. This parameter is sampled and not 100% tested. 19 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 FLASH MEMORY * Status Read Cycle tCLR CLE tCLS tCLH tCS CE tCH t WP WE tCEA tCHZ t OH tWHR RE t DH tDS I/O0 ~7 tIR tRHZ tOH tREA Status Output 70h READ1 OPERATION(READ ONE PAGE) CLE 1) On K9F2808U0B_Y or K9F2808U0B_V CE must be held low during tR CE tCEH t CHZ t OH tWC WE t WB t CRY tAR2 ALE tR tRHZ tOH tRC RE I/O 0~7 00h or 01h A0 ~ A7 A9 ~ A1 6 Column Address R/B A17 ~ A2 4 Dout N Dout N+1 Dout N+2 Dout N+3 tRR Dout 527 tRB Page(Row) Address Busy 1) NOTE : 1) is only valid on K9F2808U0B_Y or K9F2808U0B_V 20 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 FLASH MEMORY READ2 OPERATION (READ ONE PAGE) CLE On K9F2808U0B_Y or K9F2808U0B_V CE must be held low during tR CE WE tR t WB t AR2 ALE t RR I/O0 ~7 50h A 0 ~ A7 A 9 ~ A1 6 Dout 511+M A17 ~ A23 R/B Dout 511+M+1 RE Dout 527 Selected Row M Address A0 ~A 3 : Valid Address A4 ~A 7 : Dont care 512 16 Start address M PAGE PROGRAM OPERATION CLE CE t WC tWC tWC WE tWB tPROG ALE I/O0 ~7 80h A0 ~ A7 A 9 ~ A1 6 A17 ~ A2 3 Sequential Data Column Input Command Address Page(Row) Address Din N Din N+1 RE 1 up to 528 Byte Data Serial Input 10h 70h Program Command 21 I/O0 Read Status Command R/B Din 527 I/O0 =0 Successful Program I/O0 =1 Error in Program K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY BLOCK ERASE OPERATION (ERASE ONE BLOCK) CLE CE tWC WE t WB tBERS ALE RE I/O0 ~7 60h A9 ~ A 16 A1 7 ~ A2 3 DOh 70h I/O 0 Busy R/B Auto Block Erase Setup Command Page(Row) Address Erase Command Read Status Command I/O 0=0 Successful Erase I/O 0=1 Error in Erase MANUFACTURE & DEVICE ID READ OPERATION t CLR CLE CE WE ALE t AR1 RE tREA I/O 0 ~ 7 90h Read ID Command 00h ECh Address. 1cycle Maker Code 22 Device Code* Device Code Device Device Code* K9F2808Q0B 33h K9F2808U0B 73h K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY DEVICE OPERATION PAGE READ Upon initial device power up, the device status is initially Read1 command(00h) latched. This operation is also initiated by writing 00h to the command register along with three address cycles. Once the command is latched, it does not need to be written for the following page read operation. Two types of operation are available : random read, serial page read. The random read mode is enabled when the page address is changed. The 528 bytes of data within the selected page are transferred to the data registers in less than 10 s(tR). The system controller can detect the completion of this data transfer(tR) by analyzing the output of R/B pin. Once the data in a page is loaded into the registers, they may be read out by sequential RE pulse of 70ns/50n(K9F2808Q0B:70ns, K9F2808U0B:50ns) period cycle. High to low transitions of the RE clock take out the data from the selected column address up to the last column address. Read1 and Read2 commands determine pointer which selects either main area or spare area. The spare area(512 to 527 bytes) may be selectively accessed by writing the Read2 command. Addresses A0 to A3 set the starting address of spare area while addresses A4 to A7 are ignored. To move the pointer back to the main area, Read1 command(00h/01h) is needed. Figures 7 through 8 show typical sequence and timing for each read operation. Figure 7,8 details the sequence. Sequential Row Read is available only on K9F2808U0B_Y or K9F2808U0B_V : After the data of last column address is clocked out, the next page is automatically selected for sequential row read. Waiting 10 s again allows reading the selected page. The sequential row read operation is terminated by bringing CE high. Unless the operation is aborted, the page address is automatically incremented for sequential row read as in Read1 operation and spare sixteen bytes of each page may be sequentially read. The Sequential Read 1 and 2 operation is allowed only within a block and after the last page of a block is readout, the sequential read operation must be terminated by bringing CE high. When the page address moves onto the next block, read command and address must be given. Figures 7-1, 8-1 show typical sequence and timings for sequential row read operation. Figure 7. Read1 Operation CLE On K9F2808U0B_Y or K9F2808U0B_V CE must be held low during tR CE WE ALE tR R/B RE I/O 0~7 00h Start Add.(3Cycle) Data Output(Sequential) A 0 ~ A7 & A9 ~ A23 (00h Command) 1st half array (01h Command)* 2st half array Data Field Spare Field 1st half array 2st half array Data Field Spare Field * After data access on 2nd half array by 01h command, the start pointer is automatically moved to 1st half array (00h) at next cycle. 23 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY Figure 8. Read2 Operation CLE On K9F2808U0B_Y or K9F2808U0B_V CE must be held low during tR CE WE ALE tR R/B RE 50h I/O0~7 Data Output(Sequential) Start Add.(3Cycle) ( A4 ~ A7 : Dont Care) A0 ~ A 3 & A9 ~ A 2 3 Spare Field 1st half array 2nd half array Data Field Spare Field tR R/B I/O0 ~ 7 00h Start Add.(3Cycle) 01h Figure 7-1. Sequential Row Read1 Operation (only for K9F2808U0B-Y and K9F2808U0B-V, valid within a block) tR Data Output Data Output Data Output 1st 2nd (528 Byte) Nth (528 Byte) A0 ~ A 7 & A9 ~ A 2 4 (GND input=L, 00h Command) 1st half array (GND input =L, 01h Command) 2nd half array 1st half array Data Field Spare Field (GND input=H, 00h Command) 2nd half array 1st 2nd Nth Block tR 1st half array 2nd half array 1st 2nd Nth 1st 2nd Nth Data Field 24 Spare Field Data Field Spare Field K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY I/O0~7 tR tR R/B 50h Figure 8-1. Sequential Row Read2 Operation (GND Input=Fixed Low) (only for K9F2808U0B-Y and K9F2808U0B-V, valid within a block) Start Add.(3Cycle) Data Output 1st A0 ~ A 3 & A9 ~ A 2 4 tR Data Output Data Output 2nd (16Byte) Nth (16Byte) (A 4 ~ A7 : Don t Care) 1st Block Nth Data Field Spare Field PAGE PROGRAM The device is programmed basically on a page basis, but it allows multiple partial page program of one byte or consecutive bytes up to 528, in a single page program cycle. The number of consecutive partial page program operation within the same page without intervening erase operation should not exceed 2 for main array and 3 for spare array. The addressing may be done in any random order in a block. Page program cycle consists of a serial data loading(up to 528 bytes of data) into the page register, and prog ram of loaded data into the appropriate cell. Serial data loading can start in 2nd half array by moving pointer. About the pointer operation, please refer to the attached technical notes. Serial data loading is executed by entering the Serial Data Input command(80h) and three cycle address input and then serial data loading. The bytes except those to be programmed need not to be loaded. The Page Program confirm command(10h) initiates the programming process. Writing 10h alone without previously entering 80h will not initi ate program process. The internal write controller automatically executes the algorithms and timings necessary for program and verif ication, thereby freeing the CPU for other tasks. Once the program process starts, the Read Status Register command may be entered, with RE and CE low, to read the status register. The CPU can detect the completion of a program cycle by monitoring the R/B output, or the Status bit(I/O 6) of the Status Register. Only the Read Status command and Reset command are valid while programming is in progress. When the Page Program is completed, the Write Status Bit(I/O 0) may be checked(Figure 9). The internal write verification detects only errors for "1"s that are not successfully programmed to "0"s. The command register remains in Read Status command mode until another valid command is written to the command register. Figure 9 details the sequence. Figure 9. Program & Read Status Operation t PROG R/B I/O 0~7 80h Address & Data Input 10h 70h A0 ~ A7 & A 9 ~ A2 3 528 Byte Data I/O0 Fail 25 Pass K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY BLOCK ERASE The Erase operation is done on a block(16K Bytes) basis. Block Erase is executed by entering Erase Setup command(60h) and 2 cycle block addresses and Erase Confirm command(D0h). Only address A14 to A23 is valid while A9 to A13 is ignored. This twostep sequence of setup followed by execution command ensures that memory contents are not accidentally erased due to external noise condition. At the rising edge of WE after erase confirm command input, internal write controller handles erase and erase-verification. When the erase operation is completed, the Write Status Bit(I/O 0) may be checked. Figure 10 details the sequence. Figure 10. Block Erase Operation tBERS R/B I/O0~7 60h Address Input(2Cycle) I/O0 70h D0h Pass Block Add. : A 9 ~ A2 3 Fail READ STATUS The device contains a Status Register which may be read to find out whether program or erase operation is completed, and whether the program or erase operation is completed successfully. After writing 70h command to command register, a read cycle takes out the content of the Status Register to the I/O pins on the falling edge of CE or RE. This two line control allows the system to poll the progress of each device in multiple memory connections even when R/B pins are common-wired. RE or CE does not need to be toggled for updated status. Refer to table 3 for specific Status Register definitions. The command register remains in Status Read mode until further commands are issued to it. Therefore, if the status register is read during a random read cycle, a read command(00 h or 50h) should be given before sequential page read cycle. Table3. Read Status Register Definition I/O # Status I/O 0 Program / Erase Definition "0" : Successful Program / Erase "1" : Error in Program / Erase I/O 1 I/O 2 I/O 3 "0" "0" Reserved for Future Use "0" I/O 4 "0" I/O 5 "0" I/O 6 Device Operation I/O 7 Write Protect 26 "0" : Busy "1" : Ready "0" : Protected "1" : Not Protected K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY READ ID The device contains a product identification mode, initiated by writing 90h to the command register, followed by an address input of 00h. Two read cycles sequentially output the manufacture code(ECh), and the device code (73h) respectively. The command register remains in Read ID mode until further commands are issued to it. Figure 11 shows the operation sequence. Figure 11. Read ID Operation t CLR CLE t CEA CE WE tAR1 ALE t WHR RE I/O 0~7 tREA 90h 00h ECh Address. 1cycle Maker code Device Code* Device code Device Device Code* K9F2808Q0B 33h K9F2808U0B 73h RESET The device offers a reset feature, executed by writing FFh to the command register. When the device is in Busy state during random read, program or erase mode, the reset operation will abort these operations. The contents of memory cells being altered are no longer valid, as the data will be partially programmed or erased. The command register is cleared to wait for the next command, and the Status Register is cleared to value C0h when W P is high. Refer to table 4 for device status after reset operation. If the device is already in reset state, new reset command will not be accepted by the command register. The R/B pin transitions to low for tRST after the Reset command is written. Reset command is not necessary for normal operation. Refer to Figure 12 below. Figure 12. RESET Operation tRST R/B I/O 0~7 FFh Table4. Device Status Operation Mode After Power-up After Reset Read 1 Waiting for next command 27 K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY READY/BUSY The device has a R/ B output that provides a hardware method of indicating the completion of a page program, erase and random read completion. The R/B pin is normally high but transitions to low after program or erase command is written to the command register or random read is started after address loading. It returns to high when the internal controller has finished the operatio n. The pin is an open-drain driver thereby allowing two or more R/B outputs to be Or-tied. Because pull-up resistor value is related to tr(R/ B) and current drain during busy(ibusy) , an appropriate value can be obtained with the following reference chart(Fig 13). Its value c an be determined by the following guidance. Rp ibusy V CC 1.8V device - VOL : 0.1V, V OH : VCCq-0.1V 3.3V device - VOL : 0.4V, V OH : 2.4V Ready Vcc R/B open drain output VOH CL VOL Busy tf tr GND Device Fig 13 Rp vs tr ,tf & Rp vs ibusy @ Vcc = 1.8V, Ta = 25C , CL = 30pF @ Vcc = 3.3V, Ta = 25C , CL = 100pF 200n 1.7 2m tr 100n 30 0.85 120 90 60 0.57 1.7 1K tf 1.7 1.7 2K 3K Rp(ohm) tr ,tf [s] 3m Ibusy [A] tr,tf [s] 300n Ibusy 300n 200n 1.2 300 200 0.8 Rp(min, 3.3V part) = 1m 100n 0.43 100 3.6 1.7 4K 1K V CC(Max.) - V OL (Max.) IOL + IL 0.6 tf 3.6 3.6 3.6 2K 3K Rp(ohm) 4K 1.85V = 3mA + IL 3.2V V CC(Max.) - V OL(Max.) IOL + IL 2m tr Rp value guidance Rp(min, 1.8V part) = 3m = 8mA + IL where IL is the sum of the input currents of all devices tied to the R/B pin. Rp(max) is determined by maximum permissible limit of tr 28 1m Ib usy [A] 400 2.4 Ibusy K9F2808Q0B-DCB0,DIB0 K9F2808U0B-VCB0,VIB0 K9F2808U0B-YCB0,YIB0 K9F2808U0B-DCB0,DIB0 FLASH MEMORY Data Protection & Powerup sequence The device is designed to offer protection from any involuntary program/erase during power-transitions. An internal voltage detector disables all functions whenever Vcc is below about 1.1V/2V(K9F2808Q0B:1.1V, K9F2808U0B:2V). WP pin provides hardware protection and is recommended to be kept at VIL during power-up and power-down and recovery time of minimum 1s is required before internal circuit gets ready for any command sequences as shown in Figure 14. The two step command sequence for program/ erase provides additional software protection. Figure 14. AC Waveforms for Power Transition K9F2808Q0B : ~ 1.5V K9F2808U0B : ~ 2.5V VCC High WP 10s WE 29 K9F2808Q0B : ~ 1.5V K9F2808U0B : ~ 2.5V