LE25U40CQH
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4
Device Operation
The read, erase, program and other required functions of the device are executed through the command registers.
The serial I/O corrugate is shown in Figure 3 and the command list is shown in Table 2. At the falling CS
edge the
device is selected, and serial input is enabled for the commands, addresses, etc. These inputs are normalized in 8 bit
units and taken into the device interior in synchronization with the rising edge of SCK, which causes the device to
execute operation according to the command that is input.
The LE25U40CQH supports both serial interface SPI mode 0 and SPI mode 3. At the falling CS
edge, SPI mode 0 is
automatically selected if the logic level of SCK is low, and SPI mode 3 is automatically selected if the logic level of
SCK is high.
Figure 3 I/O waveforms
Table 2 Command Settings
Command 1st bus cycle 2nd bus cycle 3rd bus cycle 4th bus cycle 5th bus cycle 6th bus cycle Nth bus cycle
Read
03h A23-A16 A15-A8 A7-A0 RD *1 RD *1 RD *1
High Speed Read
0Bh A23-A16 A15-A8 A7-A0 X RD *1 RD *1
Dual Read
3Bh A23-A16 A15-A8 A7-A0 Z RD *1 RD *1
Dual I/O Read
BBh A23-A8 A7-A0,X, Z RD *1 RD *1 RD *1 RD *1
Small sector erase
20h / D7h A23-A16 A15-A8 A7-A0
Sector erase
D8h A23-A16 A15-A8 A7-A0
Chip erase
60h / C7h
Page program
02h A23-A16 A15-A8 A7-A0 PD *2 PD *2 PD *2
Write enable
06h
Write disable
04h
Power down
B9h
Status register read
05h
Status register write
01h DATA
JEDEC ID read
9Fh
ID read
ABh X X X
power down
B9h
Exit power down mode
ABh
Explanatory notes for Table 2
"X" signifies "don't care" (that is to say, any value may be input)., "Z” signifies " High Impedance ".
The "h" following each code indicates that the number given is in hexadecimal notation.
Addresses A23 to A19 for all commands are "Don't care".
*1: "RD" stands for read data. *2: "PD" stands for page program data.
CS
SCK
SO
SI
High Impedance
DATA
DATA
1st bus 2nd bus
8CLK
Mode0
Mode3
Nth bus
MSB
(Bit7)
LSB
(Bit0)