EN25QH256 Datasheet, PDF (32/74 Pages) Eon Silicon Solution Inc. – 256 Megabit Serial Flash Memory with 4Kbyte Uniform Sector

EN25QH256
Enter 4-byte mode (EN4B) (B7h)
The EN4B instruction enables accessing the address length of 32-bit for the memory area of higher
density (larger than 128Mb). The device default is in 24-bit address mode; after sending out the EN4B
instruction, the bit 2 (4 BYTE bit) of Information register will be automatically set to “1” to indicate the 4-
byte address mode has been enabled. Once the 4-byte address mode is enable, the address length
becomes 32-bit instead of the default 24-bit. There are two methods to exit the 4-byte mode: power-off
or writing exit 4-byte mode (EX4B) instruction.
All instructions are accepted normally, and just the address bit is changed form 24-bit to 32-bit.
The sequence of issuing EN4B instruction is: CS# goes low -> sending EN4B instruction to enter 4-byte
mode (automatically set 4 BYTE bit as “1”) -> CS# goes high, as shown in Figure 12.
The instruction sequence is shown in Figure 13.1 while using the Enable Quad Peripheral Interface
mode (EQPI) (38h) command.
Figure 12. Enter 4-byte mode Instruction Sequence Diagram
This Data Sheet may be revised by subsequent versions
32
or modifications due to changes in technical specifications.
©2004 Eon Silicon Solution, Inc.,
Rev. E, Issue Date: 2012/01/30
www.eonssi.com