W28V400B/T
4M(512K × 8/256K × 16)
SMARTVOLTAGE FLASH MEMORY
Table of Contents-
1. GENERAL DESCRIPTION.................................................................................................................. 3
2. FEATURES ......................................................................................................................................... 3
3. PRODUCT OVERVIEW ...................................................................................................................... 4
4. BLOCK DIAGRAM .............................................................................................................................. 5
5. PIN CONFIGURATION ....................................................................................................................... 6
6. PIN DESCRIPTION............................................................................................................................. 7
7. PRINCIPLES OF OPERATION........................................................................................................... 8
Data Protection ................................................................................................................................ 8
8. BUS OPERATION............................................................................................................................. 10
Read............................................................................................................................................... 10
Output Disable ............................................................................................................................... 10
Standby .......................................................................................................................................... 10
Deep Power-down.......................................................................................................................... 10
Read Identifier Codes Operation ................................................................................................... 11
Write............................................................................................................................................... 11
9. COMMAND DEFINITIONS................................................................................................................ 11
Read Array Command ................................................................................................................... 13
Read Identifier Codes Command................................................................................................... 13
Read Status Register Command ................................................................................................... 14
Clear Status Register Command ................................................................................................... 14
Block Erase Command .................................................................................................................. 14
Word/Byte Write Command ........................................................................................................... 15
Block Erase Suspend Command................................................................................................... 15
Word/Byte Write Suspend Command............................................................................................ 16
Considerations of Suspend............................................................................................................ 16
Block Locking................................................................................................................................. 16
10. DESIGN CONSIDERATIONS ......................................................................................................... 22
Three-line Output Control............................................................................................................... 22
RY/#BY, Block Erase and Word/Byte Write Polling....................................................................... 22
Power Supply Decoupling.............................................................................................................. 22
Publication Release Date: April 11, 2003
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Revision A4