M28W640ECT70ZB6 ,64 Mbit 4Mb x16, Boot Block 3V Supply Flash MemoryAbsolute Maximum Ratings . . . . . . . 20DC and AC PARAMETERS . 21Table 13. Operating an ..
M28W640FSB70ZA6 ,32Mbit (2Mb x16) and 64Mbit (4Mb x16) 3V Supply, Boot Block, Secure Flash Memoriesfeatures a Device Authentication mechanism. TheThe M28W320FS and M28W640FS feature KRYPTO Protectio ..
M28W640FSB70ZA6E ,32Mbit (2Mb x16) and 64Mbit (4Mb x16) 3V Supply, Boot Block, Secure Flash MemoriesFEATURES . . . . 12COMMAND INTERFACE . . . 13Read Memory Array Command . . 13Re ..
M28W640FSB70ZA6E ,32Mbit (2Mb x16) and 64Mbit (4Mb x16) 3V Supply, Boot Block, Secure Flash MemoriesFEATURES SUMMARY . . . . . 1Figure 1. Package . . . . . . . 1SUMMARY DESCRIPTION ..
M28W640FST70ZA6 ,32Mbit (2Mb x16) and 64Mbit (4Mb x16) 3V Supply, Boot Block, Secure Flash Memoriesfeatures a Device Authentication mechanism. TheThe M28W320FS and M28W640FS feature KRYPTO Protectio ..
M28W640FST-70ZA6 ,32Mbit (2Mb x16) and 64Mbit (4Mb x16) 3V Supply, Boot Block, Secure Flash MemoriesLogic Diagram . . . . . . . 6Table 2. Signal Names . . 6Figure 4. TBGA Connections (Top ..
M4T28-BR12SH1 ,TIMEKEEPER SNAPHAT (BATTERY & CRYSTAL)M4T28-BR12SHM4T32-BR12SH® ®TIMEKEEPER SNAPHAT (Battery & Crystal)
M4T32-BR12SH1 ,TIMEKEEPER SNAPHAT (BATTERY & CRYSTAL)Logic Diagram Table 1. Signal NamesX1 Crystal InputX2 Crystal OutputX1 X2V Negative VoltageBAT–V Po ..
M4T32-BR12SH6 ,TIMEKEEPER SNAPHAT (BATTERY & CRYSTAL)TABLE OF CONTENTSSUMMARY DESCRIPTION... ...... ....... ...... ....... ...... ....... ...... ...... ..
M4Z28-BR00SH1 ,ZEROPOWER SNAPHAT (BATTERY)FEATURES SUMMARY■ PROVIDES BATTERY BACKUP POWER FOR Figure 1. SNAPHAT Top PackageNON-VOLATILE ZEROP ..
M4Z32-BR00SH1 ,ZEROPOWER SNAPHAT (BATTERY)Absolute Maximum Ratings(Table2.) .... ...... ....... ...... ....... ...... ...... .....4DC AND AC ..
M500000010 , 64 Megabit (4 M x 16-Bit) and 32 Megabit (2 M x 16-Bit) CMOS 3.0 Volt-only, Simultaneous Operation Flash Memories, and 8 Mbit
M28W640ECT70N6-M28W640ECT-70N6-M28W640ECT70ZB6
64 MBIT (4MB X16, BOOT BLOCK)3V SUPPLY FLASH MEMORY
1/54February 2004
M28W640ECT
M28W640ECB64 Mbit (4Mb x16, Boot Block)
3V Supply Flash Memory
FEATURES SUMMARY SUPPLY VOLTAGE
–VDD = 2.7V to 3.6V Core Power Supply
–VDDQ= 1.65V to 3.6V for Input/Output
–VPP = 12V for fast Program (optional) ACCESS TIME: 70, 85, 90,100ns PROGRAMMING TIME: 10µs typical Double Word Programming Option Quadruple Word Programming Option COMMON FLASH INTERFACE MEMORY BLOCKS Parameter Blocks (Top or Bottom
location) Main Blocks BLOCK LOCKING All blocks locked at Power Up Any combination of blocks can be locked
–WP for Block Lock-Down SECURITY 128 bit user Programmable OTP cells 64 bit unique device identifier AUTOMATIC STAND-BY MODE PROGRAM and ERASE SUSPEND 100,000 PROGRAM/ERASE CYCLES per
BLOCK ELECTRONIC SIGNATURE Manufacturer Code: 20h Top Device Code, M28W640ECT: 8848h Bottom Device Code, M28W640ECB:
8849h
Figure 1. Packages
M28W640ECT, M28W640ECB
TABLE OF CONTENTS
FEATURES SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1Figure 1. Packages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
SUMMARY DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Figure 2. Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Table1. Signal Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Figure 3. TSOP Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Figure 4. TFBGA Connections (Top view through package) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Figure 5. Block Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Figure 6. Protection Register Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
SIGNAL DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Address Inputs (A0-A21). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Data Input/Output (DQ0-DQ15). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Chip Enable (E). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Output Enable (G). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Write Enable (W). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Write Protect (WP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Reset (RP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
VDD Supply Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
VDDQ Supply Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
VPP Program Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
VSS Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
BUS OPERATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Read. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Write. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Output Disable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Standby. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Automatic Standby. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Reset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Table2. Bus Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
COMMAND INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Read Memory Array Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Read Status Register Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Read Electronic Signature Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Table3. Command Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Read CFI Query Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Block Erase Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Program Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Double Word Program Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Quadruple Word Program Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
3/54
M28W640ECT, M28W640ECB
Clear Status Register Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Program/Erase Suspend Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Program/Erase Resume Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Protection Register Program Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Block Lock Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Block Unlock Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Block Lock-Down Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Table4. Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Table5. Read Electronic Signature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Table6. Read Block Lock Signature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Table7. Read Protection Register and Lock Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Table8. Program, Erase Times and Program/Erase Endurance Cycles . . . . . . . . . . . . . . . . . . .16
BLOCK LOCKING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Reading a Block’s Lock Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Locked State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Unlocked State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Lock-Down State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Locking Operations During Erase Suspend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17Table9. Block Lock Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Table10. Protection Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
STATUS REGISTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Program/Erase Controller Status (Bit 7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Erase Suspend Status (Bit 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Erase Status (Bit 5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Program Status (Bit 4). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
VPP Status (Bit 3). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Program Suspend Status (Bit 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Block Protection Status (Bit 1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Reserved (Bit 0). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Table11. Status Register Bits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
MAXIMUM RATING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Table12. Absolute Maximum Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
DC and AC PARAMETERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Table13. Operating and AC Measurement Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Figure 7. AC Measurement I/O Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Figure 8. AC Measurement Load Circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Table14. Capacitance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Table15. DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Figure 9. Read AC Waveforms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Table16. Read AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Figure 10.Write AC Waveforms, Write Enable Controlled. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Table17. Write AC Characteristics, Write Enable Controlled . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
M28W640ECT, M28W640ECBFigure 11.Write AC Waveforms, Chip Enable Controlled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Table18. Write AC Characteristics, Chip Enable Controlled . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Figure 12.Power-Up and Reset AC Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Table19. Power-Up and Reset AC Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
PACKAGE MECHANICAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Figure 13.TSOP48 - 48 lead Plastic Thin Small Outline, 12 x 20mm, Package Outline . . . . . . . . .29
Table20. TSOP48 - 48 lead Plastic Thin Small Outline, 12 x 20mm, Package Mechanical Data .29
Figure 14.TFBGA48 6.39x10.5mm - 8x6 ball array, 0.75mm pitch, Bottom View Package Outline30
Table21. TFBGA48 6.39x10.5mm - 8x6 ball array, 0.75mm pitch, Package Mechanical Data . . .30
Figure 15.TFBGA48 Daisy Chain - Package Connections (Top view through package) . . . . . . . .31
Figure 16.TFBGA48 Daisy Chain - PCB Connections proposal (Top view through package) . . . .31
PART NUMBERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Table22. Ordering Information Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Table23. Daisy Chain Ordering Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
APPENDIX A.BLOCK ADDRESS TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Table24. Top Boot Block Addresses, M28W640ECT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Table25. Bottom Boot Block Addresses, M28W640ECB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
APPENDIX B.COMMON FLASH INTERFACE (CFI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Table26. Query Structure Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Table27. CFI Query Identification String. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Table28. CFI Query System Interface Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Table29. Device Geometry Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Table30. Primary Algorithm-Specific Extended Query Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Table31. Security Code Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
APPENDIX C.FLOWCHARTS AND PSEUDO CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Figure 17.Program Flowchart and Pseudo Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Figure 18.Double Word Program Flowchart and Pseudo Code . . . . . . . . . . . . . . . . . . . . . . . . . . .44
Figure 19.Quadruple Word Program Flowchart and Pseudo Code. . . . . . . . . . . . . . . . . . . . . . . . .45
Figure 20.Program Suspend & Resume Flowchart and Pseudo Code . . . . . . . . . . . . . . . . . . . . . .46
Figure 21.Erase Flowchart and Pseudo Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Figure 22.Erase Suspend & Resume Flowchart and Pseudo Code . . . . . . . . . . . . . . . . . . . . . . . .48
Figure 23.Locking Operations Flowchart and Pseudo Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
Figure 24.Protection Register Program Flowchart and Pseudo Code. . . . . . . . . . . . . . . . . . . . . . .50
APPENDIX D.COMMAND INTERFACE AND PROGRAM/ERASE CONTROLLER STATE. . . . . . . .51Table32. Write State Machine Current/Next, sheet 1 of 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Table33. Write State Machine Current/Next, sheet 2 of 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
REVISION HISTORY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Table34. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
5/54
M28W640ECT, M28W640ECB
SUMMARY DESCRIPTIONThe M28W640EC is a 64 Mbit (4 Mbit x 16) non-
volatile Flash memory that can be erased electri-
cally at block level and programmed in-system on
a Word-by-Word basis using a 2.7V to 3.6V VDD
supply for the circuitry and a 1.65V to 3.6V VDDQ
supply for the Input/Output pins. An optional 12V
VPP power supply is provided to speed up custom-
er programming.
The device features an asymmetrical blocked ar-
chitecture. The M28W640EC has an array of 135
blocks: 8 Parameter Blocks of 4 KWord and 127
Main Blocks of 32 KWord. M28W640ECT has the
Parameter Blocks at the top of the memory ad-
dress space while the M28W640ECB locates the
Parameter Blocks starting from the bottom. The
memory maps are shown in Figure 5., Block Ad-
dresses.
The M28W640EC features an instant, individual
block locking scheme that allows any block to be
locked or unlocked with no latency, enabling in-
stant code and data protection. All blocks have
three levels of protection. They can be locked and
locked-down individually preventing any acciden-
tal programming or erasure. There is an additional
hardware protection against program and erase.
When VPP ≤ VPPLK all blocks are protected against
program or erase. All blocks are locked at Power
Up.
Each block can be erased separately. Erase can
be suspended in order to perform either read or
program in any other block and then resumed.
Program can be suspended to read data in any
other block and then resumed. Each block can be
programmed and erased over 100,000 cycles.
The device includes a 192 bit Protection Register
to increase the protection of a system design. The
Protection Register is divided into a 64 bit segment
and a 128 bit segment. The 64 bit segment con-
tains a unique device number written by ST, while
the second one is one-time-programmable by the
user. The user programmable segment can be
permanently protected. Figure 6., shows the Pro-
tection Register Memory Map.
Program and Erase commands are written to the
Command Interface of the memory. An on-chip
Program/Erase Controller takes care of the tim-
ings necessary for program and erase operations.
The end of a program or erase operation can be
detected and any error conditions identified. The
command set required to control the memory is
consistent with JEDEC standards.
The memory is offered in TSOP48 (12 X 20mm)
and TFBGA48 (6.39 x 10.5mm, 0.75mm pitch)
packages and is supplied with all the bits erased
(set to ’1’).
Figure 2. Logic Diagram
Table 1. Signal Names
M28W640ECT, M28W640ECB
7/54
M28W640ECT, M28W640ECB
Figure 4. TFBGA Connections (Top view through package)
M28W640ECT, M28W640ECB
9/54
M28W640ECT, M28W640ECB
SIGNAL DESCRIPTIONSSee Figure 2., Logic Diagram and Table1., Signal
Names, for a brief overview of the signals connect-
ed to this device.
Address Inputs (A0-A21). The Address Inputs
select the cells in the memory array to access dur-
ing Bus Read operations. During Bus Write opera-
tions they control the commands sent to the
Command Interface of the internal state machine.
Data Input/Output (DQ0-DQ15). The Data I/O
outputs the data stored at the selected address
during a Bus Read operation or inputs a command
or the data to be programmed during a Write Bus
operation.
Chip Enable (E). The Chip Enable input acti-
vates the memory control logic, input buffers, de-
coders and sense amplifiers. When Chip Enable is
at VILand Reset is at VIH the device is in active
mode. When Chip Enable is at VIH the memory is
deselected, the outputs are high impedance and
the power consumption is reduced to the stand-by
level.
Output Enable (G). The Output Enable controls
data outputs during the Bus Read operation of the
memory.
Write Enable (W). The Write Enable controls the
Bus Write operation of the memory’s Command
Interface. The data and address inputs are latched
on the rising edge of Chip Enable, E, or Write En-
able, W, whichever occurs first.
Write Protect (WP). Write Protect is an input
that gives an additional hardware protection for
each block. When Write Protect is at VIL, the Lock-
Down is enabled and the protection status of the
block cannot be changed. When Write Protect is at
VIH, the Lock-Down is disabled and the block can
be locked or unlocked. (refer to Table7., Read
Protection Register and Lock Register).
Reset (RP). The Reset input provides a hard-
ware reset of the memory. When Reset is at VIL,
the memory is in reset mode: the outputs are high
impedance and the current consumption is mini-
mized. After Reset all blocks are in the Locked
state. When Reset is at VIH, the device is in normal
operation. Exiting reset mode the device enters
read array mode, but a negative transition of Chip
Enable or a change of the address is required to
ensure valid data outputs.
VDD Supply Voltage. VDD provides the power
supply to the internal core of the memory device.
It is the main power supply for all operations
(Read, Program and Erase).
VDDQ Supply Voltage. VDDQ provides the
power supply to the I/O pins and enables all Out-
puts to be powered independently from VDD. VDDQ
can be tied to VDD or can use a separate supply.
VPP Program Supply Voltage. VPP is both a
control input and a power supply pin. The two
functions are selected by the voltage range ap-
plied to the pin. The Supply Voltage VDD and the
Program Supply Voltage VPP can be applied in
any order.
If VPP is kept in a low voltage range (0V to 3.6V)
VPP is seen as a control input. In this case a volt-
age lower than VPPLK gives an absolute protection
against program or erase, while VPP > VPP1 en-
ables these functions (see Table 15., DC Charac-
teristics, for the relevant values). VPP is only
sampled at the beginning of a program or erase; a
change in its value after the operation has started
does not have any effect on Program or Erase,
however for Double or Quadruple Word Program
the results are uncertain.
If VPP is in the range 11.4V to 12.6V it acts as a
power supply pin. In this condition VPP must be
stable until the Program/Erase algorithm is com-
pleted (see Table 17. and Table 18.).
VSS Ground. VSS is the reference for all voltage
measurements.
Note: Each device in a system should have
VDD, VDDQ and VPP decoupled with a 0.1µF ca-
pacitor close to the pin. See Figure 8., AC Mea-
surement Load Circuit. The PCB track widths
should be sufficient to carry the required VPP
program and erase currents.
M28W640ECT, M28W640ECB
BUS OPERATIONSThere are six standard bus operations that control
the device. These are Bus Read, Bus Write, Out-
put Disable, Standby, Automatic Standby and Re-
set. See Table2., Bus Operations, for a summary.
Typically glitches of less than 5ns on Chip Enable
or Write Enable are ignored by the memory and do
not affect bus operations.
Read. Read Bus operations are used to output
the contents of the Memory Array, the Electronic
Signature, the Status Register and the Common
Flash Interface. Both Chip Enable and Output En-
able must be at VIL in order to perform a read op-
eration. The Chip Enable input should be used to
enable the device. Output Enable should be used
to gate data onto the output. The data read de-
pends on the previous command written to the
memory (see Command Interface section). See
Figure 9., Read AC Waveforms, and
Table 16., Read AC Characteristics, for details of
when the output becomes valid.
Read mode is the default state of the device when
exiting Reset or after power-up.
Write. Bus Write operations write Commands to
the memory or latch Input Data to be programmed.
A write operation is initiated when Chip Enable
and Write Enable are at VIL with Output Enable at
VIH. Commands, Input Data and Addresses are
latched on the rising edge of Write Enable or Chip
Enable, whichever occurs first.
See Figure 10. and Figure 11., Write AC Wave-
forms, and Table 17. and Table 18., Write AC
Characteristics, for details of the timing require-
ments.
Output Disable. The data outputs are high im-
pedance when the Output Enable is at VIH.
Standby. Standby disables most of the internal
circuitry allowing a substantial reduction of the cur-
rent consumption. The memory is in stand-by
when Chip Enable is at VIH and the device is in
read mode. The power consumption is reduced to
the stand-by level and the outputs are set to high
impedance, independently from the Output Enable
or Write Enable inputs. If Chip Enable switches to
VIH during a program or erase operation, the de-
vice enters Standby mode when finished.
Automatic Standby. Automatic Standby pro-
vides a low power consumption state during Read
mode. Following a read operation, the device en-
ters Automatic Standby after 150ns of bus inactiv-
ity even if Chip Enable is Low, VIL, and the supply
current is reduced to IDD1. The data Inputs/Out-
puts will still output data if a bus Read operation is
in progress.
Reset. During Reset mode when Output Enable
is Low, VIL, the memory is deselected and the out-
puts are high impedance. The memory is in Reset
mode when Reset is at VIL. The power consump-
tion is reduced to the Standby level, independently
from the Chip Enable, Output Enable or Write En-
able inputs. If Reset is pulled to VSS during a Pro-
gram or Erase, this operation is aborted and the
memory content is no longer valid.
Table 2. Bus Operations Note: X = VIL or VIH, VPPH = 12V ± 5%.
11/54
M28W640ECT, M28W640ECB
COMMAND INTERFACEAll Bus Write operations to the memory are inter-
preted by the Command Interface. Commands
consist of one or more sequential Bus Write oper-
ations. An internal Program/Erase Controller han-
dles all timings and verifies the correct execution
of the Program and Erase commands. The Pro-
gram/Erase Controller provides a Status Register
whose output may be read at any time during, to
monitor the progress of the operation, or the Pro-
gram/Erase states. See Table3., Command
Codes, for a summary of the commands and see
APPENDIX D., Table 32., Write State Machine
Current/Next, sheet 1 of 2., for a summary of the
Command Interface.
The Command Interface is reset to Read mode
when power is first applied, when exiting from Re-
set or whenever VDD is lower than VLKO. Com-
mand sequences must be followed exactly. Any
invalid combination of commands will reset the de-
vice to Read mode. Refer to Table4., Commands,
in conjunction with the text descriptions below.
Read Memory Array Command The Read command returns the memory to its
Read mode. One Bus Write cycle is required to is-
sue the Read Memory Array command and return
the memory to Read mode. Subsequent read op-
erations will read the addressed location and out-
put the data. When a device Reset occurs, the
memory defaults to Read mode.
Read Status Register Command The Status Register indicates when a program or
erase operation is complete and the success or
failure of the operation itself. Issue a Read Status
Register command to read the Status Register’s
contents. Subsequent Bus Read operations read
the Status Register at any address, until another
command is issued. See Table 11., Status Regis-
ter Bits, for details on the definitions of the bits.
The Read Status Register command may be is-
sued at any time, even during a Program/Erase
operation. Any Read attempt during a Program/
Erase operation will automatically output the con-
tent of the Status Register.
Read Electronic Signature Command The Read Electronic Signature command reads
the Manufacturer and Device Codes and the Block
Locking Status, or the Protection Register.
The Read Electronic Signature command consists
of one write cycle, a subsequent read will output
the Manufacturer Code, the Device Code, the
Block Lock and Lock-Down Status, or the Protec-
tion and Lock Register. See Tables 5, 6 and 7 for
the valid address.
Table 3. Command Codes
Read CFI Query Command The Read Query Command is used to read data
from the Common Flash Interface (CFI) Memory
Area, allowing programming equipment or appli-
cations to automatically match their interface to
the characteristics of the device. One Bus Write
cycle is required to issue the Read Query Com-
mand. Once the command is issued subsequent
Bus Read operations read from the Common
Flash Interface Memory Area. See APPENDIX
B., COMMON FLASH INTERFACE (CFI), Tables
26, 27, 28, 29, 30 and 31 for details on the infor-
mation contained in the Common Flash Interface
memory area.
Block Erase Command The Block Erase command can be used to erase
a block. It sets all the bits within the selected block
to ’1’. All previous data in the block is lost. If the
block is protected then the Erase operation will
abort, the data in the block will not be changed and
the Status Register will output the error.
Two Bus Write cycles are required to issue the
command. The first bus cycle sets up the Erase
command.
M28W640ECT, M28W640ECB The second latches the block address in the
internal state machine and starts the Program/
Erase Controller.
If the second bus cycle is not Write Erase Confirm
(D0h), Status Register bits b4 and b5 are set and
the command aborts.
Erase aborts if Reset turns to VIL. As data integrity
cannot be guaranteed when the Erase operation is
aborted, the block must be erased again.
During Erase operations the memory will accept
the Read Status Register command and the Pro-
gram/Erase Suspend command, all other com-
mands will be ignored. Typical Erase times are
given in Table8., Program, Erase Times and Pro-
gram/Erase Endurance Cycles.
See APPENDIX C., Figure 21., Erase Flowchart
and Pseudo Code, for a suggested flowchart for
using the Erase command.
Program Command The memory array can be programmed word-by-
word. Two bus write cycles are required to issue
the Program Command. The first bus cycle sets up the Program
command. The second latches the Address and the Data
to be written and starts the Program/Erase
Controller.
During Program operations the memory will ac-
cept the Read Status Register command and the
Program/Erase Suspend command. Typical Pro-
gram times are given in Table8., Program, Erase
Times and Program/Erase Endurance Cycles.
Programming aborts if Reset goes to VIL. As data
integrity cannot be guaranteed when the program
operation is aborted, the block containing the
memory location must be erased and repro-
grammed.
See APPENDIX C., Figure 17., Program Flow-
chart and Pseudo Code, for the flowchart for using
the Program command.
Double Word Program Command This feature is offered to improve the programming
throughput, writing a page of two adjacent words
in parallel.The two words must differ only for the
address A0. Programming should not be attempt-
ed when VPP is not at VPPH.
Three bus write cycles are necessary to issue the
Double Word Program command. The first bus cycle sets up the Double Word
Program Command. The second bus cycle latches the Address and
the Data of the first word to be written. The third bus cycle latches the Address and
the Data of the second word to be written and
starts the Program/Erase Controller.
Read operations output the Status Register con-
tent after the programming has started. Program-
ming aborts if Reset goes to VIL. As data integrity
cannot be guaranteed when the program opera-
tion is aborted, the block containing the memory
location must be erased and reprogrammed.
See APPENDIX C., Figure 18., Double Word Pro-
gram Flowchart and Pseudo Code for the flow-
chart for using the Double Word Program
command.
Quadruple Word Program Command This feature is offered to improve the programming
throughput, writing a page of four adjacent words
in parallel.The four words must differ only for the
addresses A0 and A1. Programming should not be
attempted when VPP is not at VPPH.
Five bus write cycles are necessary to issue the
Quadruple Word Program command. The first bus cycle sets up the Quadruple
Word Program Command. The second bus cycle latches the Address and
the Data of the first word to be written. The third bus cycle latches the Address and
the Data of the second word to be written. The fourth bus cycle latches the Address and
the Data of the third word to be written. The fifth bus cycle latches the Address and the
Data of the fourth word to be written and starts
the Program/Erase Controller.
Read operations output the Status Register con-
tent after the programming has started. Program-
ming aborts if Reset goes to VIL. As data integrity
cannot be guaranteed when the program opera-
tion is aborted, the block containing the memory
location must be erased and reprogrammed.
See APPENDIX C., Figure 19., Quadruple Word
Program Flowchart and Pseudo Code, for the
flowchart for using the Quadruple Word Program
command.
Clear Status Register Command The Clear Status Register command can be used
to reset bits 1, 3, 4 and 5 in the Status Register to
‘0’. One bus write cycle is required to issue the
Clear Status Register command.
The bits in the Status Register do not automatical-
ly return to ‘0’ when a new Program or Erase com-
mand is issued. The error bits in the Status
Register should be cleared before attempting a
new Program or Erase command.
Program/Erase Suspend Command The Program/Erase Suspend command is used to
pause a Program or Erase operation. One bus
write cycle is required to issue the Program/Erase
command and pause the Program/Erase control-
ler.
13/54
M28W640ECT, M28W640ECBDuring Program/Erase Suspend the Command In-
terface will accept the Program/Erase Resume,
Read Array, Read Status Register, Read Electron-
ic Signature and Read CFI Query commands. Ad-
ditionally, if the suspend operation was Erase then
the Program, Double Word Program, Quadruple
Word Program, Block Lock, Block Lock-Down or
Protection Program commands will also be ac-
cepted. The block being erased may be protected
by issuing the Block Protect, Block Lock or Protec-
tion Program commands. When the Program/
Erase Resume command is issued the operation
will complete. Only the blocks not being erased
may be read or programmed correctly.
During a Program/Erase Suspend, the device can
be placed in a pseudo-standby mode by taking
Chip Enable to VIH. Program/Erase is aborted if
Reset turns to VIL.
See APPENDIX C., Figure 20., Program Suspend
& Resume Flowchart and Pseudo Code, and Fig-
ure 22., Erase Suspend & Resume Flowchart and
Pseudo Code, for flowcharts for using the Pro-
gram/Erase Suspend command.
Program/Erase Resume Command The Program/Erase Resume command can be
used to restart the Program/Erase Controller after
a Program/Erase Suspend operation has paused
it. One Bus Write cycle is required to issue the
command. Once the command is issued subse-
quent Bus Read operations read the Status Reg-
ister.
See APPENDIX C., Figure 20., Program Suspend
& Resume Flowchart and Pseudo Code, and Fig-
ure 22., Erase Suspend & Resume Flowchart and
Pseudo Code, for flowcharts for using the Pro-
gram/Erase Resume command.
Protection Register Program CommandThe Protection Register Program command is
used to Program the 128 bit user One-Time-Pro-
grammable (OTP) segment of the Protection Reg-
ister. The segment is programmed 16 bits at a
time. When shipped all bits in the segment are set
to ‘1’. The user can only program the bits to ‘0’.
Two write cycles are required to issue the Protec-
tion Register Program command. The first bus cycle sets up the Protection
Register Program command. The second latches the Address and the Data
to be written to the Protection Register and
starts the Program/Erase Controller.
Read operations output the Status Register con-
tent after the programming has started.
The segment can be protected by programming bit
1 of the Protection Lock Register (see Figure
6., Protection Register Memory Map). Attempting
to program a previously protected Protection Reg-
ister will result in a Status Register error. The pro-
tection of the Protection Register is not reversible.
The Protection Register Program cannot be sus-
pended.
Block Lock CommandThe Block Lock command is used to lock a block
and prevent Program or Erase operations from
changing the data in it. All blocks are locked at
power-up or reset.
Two Bus Write cycles are required to issue the
Block Lock command. The first bus cycle sets up the Block Lock
command. The second Bus Write cycle latches the block
address.
The lock status can be monitored for each block
using the Read Electronic Signature command.
Table 10. shows the protection status after issuing
a Block Lock command.
The Block Lock bits are volatile, once set they re-
main set until a hardware reset or power-down/
power-up. They are cleared by a Blocks Unlock
command. Refer to the section, Block Locking, for
a detailed explanation.
Block Unlock CommandThe Blocks Unlock command is used to unlock a
block, allowing the block to be programmed or
erased. Two Bus Write cycles are required to is-
sue the Blocks Unlock command. The first bus cycle sets up the Block Unlock
command. The second Bus Write cycle latches the block
address.
The lock status can be monitored for each block
using the Read Electronic Signature command.
Table 10. shows the protection status after issuing Block Unlock command. Refer to the section,
Block Locking, for a detailed explanation.
Block Lock-Down CommandA locked block cannot be Programmed or Erased,
or have its protection status changed when WP is
low, VIL. When WP is high, VIH, the Lock-Down
function is disabled and the locked blocks can be
individually unlocked by the Block Unlock com-
mand.
Two Bus Write cycles are required to issue the
Block Lock-Down command. The first bus cycle sets up the Block Lock
command. The second Bus Write cycle latches the block
address.
The lock status can be monitored for each block
using the Read Electronic Signature command.
Locked-Down blocks revert to the locked (and not
M28W640ECT, M28W640ECBlocked-down) state when the device is reset on
power-down. Table 10. shows the protection sta-
tus after issuing a Block Lock-Down command.
Refer to the section, Block Locking, for a detailed
explanation.
Table 4. CommandsNote:1. X = Don’t Care, RA=Read Address, RD=Read Data, SRD=Status Register Data, ID=Identifier (Manufacture and Device Code),
QA=Query Address, QD=Query Data, BA=Block Address, PA=Program Address, PD=Program Data, PRA=Protection Register Ad-
dress, PRD=Protection Register Data. The signature addresses are listed in Tables 5, 6 and 7. Program Addresses 1 and 2 must be consecutive Addresses differing only for A0. Program Addresses 1,2,3 and 4 must be consecutive Addresses differing only for A0 and A1.
Table 5. Read Electronic Signature Note: RP = VIH.
15/54
M28W640ECT, M28W640ECB
Table 6. Read Block Lock Signature Note:1. A Locked-Down Block can be locked "DQ0 = 1" or unlocked "DQ0 = 0"; see Block Locking section.
Table 7. Read Protection Register and Lock Register
M28W640ECT, M28W640ECB
Table 8. Program, Erase Times and Program/Erase Endurance CyclesNote:1. Typical time to program a Main or Parameter Block using the Double Word Program and the Quadruple Word Program commands
respectively.
BLOCK LOCKINGThe M28W640EC features an instant, individual
block locking scheme that allows any block to be
locked or unlocked with no latency. This locking
scheme has three levels of protection. Lock/Unlock - this first level allows software-
only control of block locking. Lock-Down - this second level requires
hardware interaction before locking can be
changed. VPP ≤ VPPLK - the third level offers a complete
hardware protection against program and
erase on all blocks.
The protection status of each block can be set to
Locked, Unlocked, and Lock-Down. Table 10., de-
fines all of the possible protection states (WP,
DQ1, DQ0), and APPENDIX C., Figure 23., shows
a flowchart for the locking operations.
Reading a Block’s Lock StatusThe lock status of every block can be read in the
Read Electronic Signature mode of the device. To
enter this mode write 90h to the device. Subse-
quent reads at the address specified in Table6.,
will output the protection status of that block. The
lock status is represented by DQ0 and DQ1. DQ0
indicates the Block Lock/Unlock status and is set
by the Lock command and cleared by the Unlock
command. It is also automatically set when enter-
ing Lock-Down. DQ1 indicates the Lock-Down sta-
tus and is set by the Lock-Down command. It
cannot be cleared by software, only by a hardware
reset or power-down.
The following sections explain the operation of the
locking system.
Locked StateThe default status of all blocks on power-up or af-
ter a hardware reset is Locked (states (0,0,1) or
(1,0,1)). Locked blocks are fully protected from
any program or erase. Any program or erase oper-
ations attempted on a locked block will return an
error in the Status Register. The Status of a
Locked block can be changed to Unlocked or
Lock-Down using the appropriate software com-
mands. An Unlocked block can be Locked by issu-
ing the Lock command.
Unlocked StateUnlocked blocks (states (0,0,0), (1,0,0) (1,1,0)),
can be programmed or erased. All unlocked
blocks return to the Locked state after a hardware
reset or when the device is powered-down. The
status of an unlocked block can be changed to
Locked or Locked-Down using the appropriate
software commands. A locked block can be un-
locked by issuing the Unlock command.
17/54
M28W640ECT, M28W640ECB
Lock-Down StateBlocks that are Locked-Down (state (0,1,x))are
protected from program and erase operations (as
for Locked blocks) but their protection status can-
not be changed using software commands alone.
A Locked or Unlocked block can be Locked-Down
by issuing the Lock-Down command. Locked-
Down blocks revert to the Locked state when the
device is reset or powered-down.
The Lock-Down function is dependent on the WP
input pin. When WP=0 (VIL), the blocks in the
Lock-Down state (0,1,x) are protected from pro-
gram, erase and protection status changes. When
WP=1 (VIH) the Lock-Down function is disabled
(1,1,1) and Locked-Down blocks can be individu-
ally unlocked to the (1,1,0) state by issuing the
software command, where they can be erased and
programmed. These blocks can then be relocked
(1,1,1) and unlocked (1,1,0) as desired while WP
remains high. When WP is low , blocks that were
previously Locked-Down return to the Lock-Down
state (0,1,x) regardless of any changes made
while WP was high. Device reset or power-down
resets all blocks , including those in Lock-Down, to
the Locked state.
Locking Operations During Erase SuspendChanges to block lock status can be performed
during an erase suspend by using the standard
locking command sequences to unlock, lock or
lock-down a block. This is useful in the case when
another block needs to be updated while an erase
operation is in progress.
To change block locking during an erase opera-
tion, first write the Erase Suspend command, then
check the status register until it indicates that the
erase operation has been suspended. Next write
the desired Lock command sequence to a block
and the lock status will be changed. After complet-
ing any desired lock, read, or program operations,
resume the erase operation with the Erase Re-
sume command.
If a block is locked or locked-down during an erase
suspend of the same block, the locking status bits
will be changed immediately, but when the erase
is resumed, the erase operation will complete.
Locking operations cannot be performed during a
program suspend. Refer to APPENDIX D., Com-
mand Interface and Program/Erase Controller
State, for detailed information on which com-
mands are valid during erase suspend.
Table 9. Block Lock Status
Table 10. Protection Status Note:1. The lock status is defined by the write protect pin and by DQ1 (‘1’ for a locked-down block) and DQ0 (‘1’ for a locked block) as read
in the Read Electronic Signature command with A1 = VIH and A0 = VIL. All blocks are locked at power-up, so the default configuration is 001 or 101 according to WP status. A WP transition to VIH on a locked block will restore the previous DQ0 value, giving a 111 or 110.
M28W640ECT, M28W640ECB
STATUS REGISTERThe Status Register provides information on the
current or previous Program or Erase operation.
The various bits convey information and errors on
the operation. To read the Status register the
Read Status Register command can be issued, re-
fer to Read Status Register Command section. To
output the contents, the Status Register is latched
on the falling edge of the Chip Enable or Output
Enable signals, and can be read until Chip Enable
or Output Enable returns to VIH. Either Chip En-
able or Output Enable must be toggled to update
the latched data.
Bus Read operations from any address always
read the Status Register during Program and
Erase operations.
The bits in the Status Register are summarized in
Table 11., Status Register Bits. Refer to Table11.
in conjunction with the following text descriptions.
Program/Erase Controller Status (Bit 7). The Pro-
gram/Erase Controller Status bit indicates whether
the Program/Erase Controller is active or inactive.
When the Program/Erase Controller Status bit is
Low (set to ‘0’), the Program/Erase Controller is
active; when the bit is High (set to ‘1’), the Pro-
gram/Erase Controller is inactive, and the device
is ready to process a new command.
The Program/Erase Controller Status is Low im-
mediately after a Program/Erase Suspend com-
mand is issued until the Program/Erase Controller
pauses. After the Program/Erase Controller paus-
es the bit is High .
During Program, Erase, operations the Program/
Erase Controller Status bit can be polled to find the
end of the operation. Other bits in the Status Reg-
ister should not be tested until the Program/Erase
Controller completes the operation and the bit is
High.
After the Program/Erase Controller completes its
operation the Erase Status, Program Status, VPP
Status and Block Lock Status bits should be tested
for errors.
Erase Suspend Status (Bit 6). The Erase Sus-
pend Status bit indicates that an Erase operation
has been suspended or is going to be suspended.
When the Erase Suspend Status bit is High (set to
‘1’), a Program/Erase Suspend command has
been issued and the memory is waiting for a Pro-
gram/Erase Resume command.
The Erase Suspend Status should only be consid-
ered valid when the Program/Erase Controller Sta-
tus bit is High (Program/Erase Controller inactive).
Bit 7 is set within 30µs of the Program/Erase Sus-
pend command being issued therefore the memo-
ry may still complete the operation rather than
entering the Suspend mode.
When a Program/Erase Resume command is is-
sued the Erase Suspend Status bit returns Low.
Erase Status (Bit 5). The Erase Status bit can be
used to identify if the memory has failed to verify
that the block has erased correctly. When the
Erase Status bit is High (set to ‘1’), the Program/
Erase Controller has applied the maximum num-
ber of pulses to the block and still failed to verify
that the block has erased correctly. The Erase Sta-
tus bit should be read once the Program/Erase
Controller Status bit is High (Program/Erase Con-
troller inactive).
Once set High, the Erase Status bit can only be re-
set Low by a Clear Status Register command or a
hardware reset. If set High it should be reset be-
fore a new Program or Erase command is issued,
otherwise the new command will appear to fail.
Program Status (Bit 4). The Program Status bit
is used to identify a Program failure. When the
Program Status bit is High (set to ‘1’), the Pro-
gram/Erase Controller has applied the maximum
number of pulses to the byte and still failed to ver-
ify that it has programmed correctly. The Program
Status bit should be read once the Program/Erase
Controller Status bit is High (Program/Erase Con-
troller inactive).
Once set High, the Program Status bit can only be
reset Low by a Clear Status Register command or
a hardware reset. If set High it should be reset be-
fore a new command is issued, otherwise the new
command will appear to fail.
VPP Status (Bit 3). The VPP Status bit can be
used to identify an invalid voltage on the VPP pin
during Program and Erase operations. The VPP
pin is only sampled at the beginning of a Program
or Erase operation. Indeterminate results can oc-
cur if VPP becomes invalid during an operation.
When the VPP Status bit is Low (set to ‘0’), the volt-
age on the VPP pin was sampled at a valid voltage;
when the VPP Status bit is High (set to ‘1’), the VPP
pin has a voltage that is below the VPP Lockout
Voltage, VPPLK, the memory is protected and Pro-
gram and Erase operations cannot be performed.
Once set High, the VPP Status bit can only be reset
Low by a Clear Status Register command or a
hardware reset. If set High it should be reset be-
fore a new Program or Erase command is issued,
otherwise the new command will appear to fail.
Program Suspend Status (Bit 2). The Program
Suspend Status bit indicates that a Program oper-
ation has been suspended. When the Program
Suspend Status bit is High (set to ‘1’), a Program/
Erase Suspend command has been issued and
the memory is waiting for a Program/Erase Re-
sume command. The Program Suspend Status
should only be considered valid when the Pro-
19/54
M28W640ECT, M28W640ECBgram/Erase Controller Status bit is High (Program/
Erase Controller inactive). Bit 2 is set within 5µs of
the Program/Erase Suspend command being is-
sued therefore the memory may still complete the
operation rather than entering the Suspend mode.
When a Program/Erase Resume command is is-
sued the Program Suspend Status bit returns Low.
Block Protection Status (Bit 1). The Block Pro-
tection Status bit can be used to identify if a Pro-
gram or Erase operation has tried to modify the
contents of a locked block.
When the Block Protection Status bit is High (set
to ‘1’), a Program or Erase operation has been at-
tempted on a locked block.
Once set High, the Block Protection Status bit can
only be reset Low by a Clear Status Register com-
mand or a hardware reset. If set High it should be
reset before a new command is issued, otherwise
the new command will appear to fail.
Reserved (Bit 0). Bit 0 of the Status Register is
reserved. Its value must be masked.
Note: Refer to APPENDIX C., FLOWCHARTS
AND PSEUDO CODES, for using the Status
Register.
Table 11. Status Register BitsNote: Logic level ’1’ is High, ’0’ is Low.
M28W640ECT, M28W640ECB
MAXIMUM RATINGStressing the device above the rating listed in the
Absolute Maximum Ratings table may cause per-
manent damage to the device. These are stress
ratings only and operation of the device at these or
any other conditions above those indicated in the
Operating sections of this specification is not im-
plied. Exposure to Absolute Maximum Rating con-
ditions for extended periods may affect device
reliability. Refer also to the STMicroelectronics
SURE Program and other relevant quality docu-
ments.
Table 12. Absolute Maximum RatingsNote:1. Depends on range.
21/54
M28W640ECT, M28W640ECB
DC AND AC PARAMETERSThis section summarizes the operating and mea-
surement conditions, and the DC and AC charac-
teristics of the device. The parameters in the DC
and AC characteristics Tables that follow, are de-
rived from tests performed under the Measure-
ment Conditions summarized in
Table 13., Operating and AC Measurement Con-
ditions. Designers should check that the operating
conditions in their circuit match the measurement
conditions when relying on the quoted parame-
ters.
Table 13. Operating and AC Measurement Conditions
Figure 7. AC Measurement I/O Waveform
Table 14. CapacitanceNote: Sampled only, not 100% tested.
M28W640ECT, M28W640ECB
Table 15. DC Characteristics
23/54
M28W640ECT, M28W640ECB
Figure 9. Read AC Waveforms
Table 16. Read AC Characteristics Note:1. Sampled only, not 100% tested. G may be delayed by up to tELQV - tGLQV after the falling edge of E without increasing tELQV.
M28W640ECT, M28W640ECB
25/54
M28W640ECT, M28W640ECB
Table 17. Write AC Characteristics, Write Enable Controlled Note:1. Sampled only, not 100% tested. Applicable if VPP is seen as a logic input (VPP < 3.6V).
M28W640ECT, M28W640ECB
Figure 11. Write AC Waveforms, Chip Enable Controlled
27/54
M28W640ECT, M28W640ECB
Table 18. Write AC Characteristics, Chip Enable Controlled Note:1. Sampled only, not 100% tested. Applicable if VPP is seen as a logic input (VPP < 3.6V).
