This Data Sheet may be revised by subsequent versions

©2004 Eon Silicon Solution, Inc.,

www.eonssi.com

or modifications due to changes in technical specifications.

10

EN25LF20

Rev. D, Issue Date: 2010/05/31

Write Enable (WREN) (06h)

The Write Enable (WREN) instruction (Figure 5) sets the Write Enable Latch (WEL) bit. The Write

Enable Latch (WEL) bit must be set prior to every Page Program (PP), Sector Erase (SE), Block Erase

(BE), Chip Erase (CE) and Write Status Register (WRSR) instruction.

The Write Enable (WREN) instruction is entered by driving Chip Select (CS#) Low, sending the

instruction code, and then driving Chip Select (CS#) High.

Figure 5. Write Enable Instruction Sequence Diagram

Write Disable (WRDI) (04h)

The Write Disable instruction (Figure 6) resets the Write Enable Latch (WEL) bit in the Status Register

to a 0 or exit from OTP mode to normal mode. The Write Disable instruction is entered by driving Chip

Select (CS#) low, shifting the instruction code “04h” into the DI pin and then driving Chip Select (CS#)

high. Note that the WEL bit is automatically reset after Power-up and upon completion of the Write

Status Register, Page Program, Sector Erase, Block Erase (BE) and Chip Erase instructions.

Figure 6. Write Disable Instruction Sequence Diagram