R1EX25512ASA00A/R1EX25512ATA00A

Write Enable (WREN):

The Write Enable Latch (WEL) bit must be set prior to each WRITE and WRSR instruction. The only way to do this is

to send a Write Enable instruction to the device. As shown in the following figure, to send this instruction to the device,

chip select (

S) is driven low, and the bits of the instruction byte are shifted in, on serial data input (D). The device then

enters a wait state. It waits for the device to be deselected, by chip select (

S) being driven high.

Write Enable (WREN) Sequence

S

W

C

D

Q

Instruction

01

2

3

4

5

6

High-Z

7

R10DS0046EJ0200 Rev.2.00

Page 10 of 20

Oct.04, 2010