km29w040ait Samsung Semiconductor, Inc., km29w040ait Datasheet - Page 21

• Manufacturer Part Number: km29w040ait
• Description: 512k X 8 Bit Nand Flash Memory
• Manufacturer: Samsung Semiconductor, Inc.

READ ID
The device contains a product identification mode, initiated by writing 90H to the command register, followed by an address input of
00H. Two read cycles sequentially output the manufacture code(ECH), and the device code (A4H). The command register remains
in Read ID mode until further commands are issued to it. Figure 9 shows the operation sequence.
DATA PROTECTTION
The device is designed to offer protection from any involuntary program/erase during power-transitions. An internal voltage detector
disables all functions whenever Vcc is below about 2V. WP pin provides hardware protection and is recommended to be kept at V
during power-up and power-down as shown in Figure 8. The two step command sequence for program/erase provides additional
software protection.
KM29W040AT, KM29W040AIT
Figure 8. AC Waveforms for Power Transition
Figure 9. Read ID Operation
CLE
CE
WE
ALE
RE
I/O
V
WP
CC
0
~
7
90H
~ 2.5V
Add. Input(1Cycle)
A
0
~A
7
:"0"
High
t
WHRID
t
AR
t
21
CR
t
REA
Dout(ECH)
Maker code
FLASH MEMORY
Device code
Dout(
~ 2.5V
A4H
)
IL