Pin Functions
Function Logic
Command Settings
Notes on command settings
1. X = high or low
2. The sector address is taken from A8 to A18, the sector size is 256 bytes, and A0 to A7 can be high or low during a sector erase operation.
3. The program address is taken from A0 to A18.
4. Data is displayed in hexadecimal.
5. SDP refers to the software data protect function, which uses a 7-byte read cycle sequence.
Y = Can be executed even when the software data protect function is enabled.
N = Cannot be executed when the software data protect function is enabled.
6. Figures 9 and 10 show the operation of the software data protect function using 7-byte read cycle sequences.
7. When an address of 0000 is specified, the manufacturer code, BF, is output, and when the address is 0001, the device code, 04, is output.
No. 5468-3/14
LE28FV4001M, T, R-20/25
Symbol Pin Functions
A18 to A0 Address input
Supply the memory address to these pins.
The address is latched internally during a write cycle.
These pins output data during a read cycle and input data during a write cycle.
DQ7 to DQ0 Data input and output Data is latched internally during a write cycle.
Outputs go to the high-impedance state when either OE or CE is high.
CE Chip enable
The device is active when CE is low.
When CE is high, the device becomes unselected and goes to the standby state.
OE Output enable
Makes the data output buffers active.
OE is a low-active input.
WE Write enable
Makes the write operation active.
WE is an active-low input.
V
DD
Power supply Apply 3.3 V ±0.3 V to this pin.
V
SS
Ground
N.C. No connection These pins are not connected to the chip internally.
Mode CE OE WE A18 to A0 DQ7 to DQ0
Read V
IL
V
IL
VIHA
IN
D
OUT
Write V
IL
V
IH
VILA
IN
D
IN
Standby or write inhibit V
IH
X X X High-Z
Write inhibit
X V
IL
X X High-Z/D
OUT
X X VIHX High-Z/D
OUT
A18 to A10 = VIL, A8 to A1 = VIL,
Manufacturer code (BF)
Product identification V
IL
V
IL
V
IH
A9 = 12 V, A0 = V
IL
A18 to A10 = VIL, A8 to A1 = VIL,
Device code (04)
A9 = 12 V, A0 = V
IH
Command
Request Setup command cycle Execute command cycle
SDP
cycles Operation Address Data Operation Address Data
Sector erase 2 Write X 20H Write Sector address D0H N
Byte program 2 Write X 10H Write Program address Program data N
Reset 1 Write X FFH Y
Read ID 3 Write X 90H Read (7) (7) Y
Software data unprotect 7 See Figure 9.
Software data protect 7 See Figure 10.