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NAND512-B, NAND01G-B, NAND02G-B, NAND04G-B, NAND08G-B
BUS OPERATIONS
There are six standard bus operations that control
the memory. Each of these is described in this
mary.
Typically, glitches of less than 5 ns on Chip En-
able, Write Enable and Read Enable are ignored
by the memory and do not affect bus operations.
Command Input
Command Input bus operations are used to give
commands to the memory. Commands are ac-
cepted when Chip Enable is Low, Command Latch
Enable is High, Address Latch Enable is Low and
Read Enable is High. They are latched on the ris-
ing edge of the Write Enable signal.
Only I/O0 to I/O7 are used to input commands.
ings requirements.
Address Input
Address Input bus operations are used to input the
memory addresses. Four bus cycles are required
to input the addresses for the 512Mb and 1Gb de-
vices whereas five bus cycles are required for the
2Gb, 4Gb and 8Gb devices (refer to
Table 6. and
The addresses are accepted when Chip Enable is
Low, Address Latch Enable is High, Command
Latch Enable is Low and Read Enable is High.
They are latched on the rising edge of the Write
Enable signal. Only I/O0 to I/O7 are used to input
addresses.
ings requirements.
Data Input
Data Input bus operations are used to input the
data to be programmed.
Data is accepted only when Chip Enable is Low,
Address Latch Enable is Low, Command Latch
Enable is Low and Read Enable is High. The data
is latched on the rising edge of the Write Enable
signal. The data is input sequentially using the
Write Enable signal.
tails of the timings requirements.
Data Output
Data Output bus operations are used to read: the
data in the memory array, the Status Register, the
lock status, the Electronic Signature and the
Unique Identifier.
Data is output when Chip Enable is Low, Write En-
able is High, Address Latch Enable is Low, and
Command Latch Enable is Low.
The data is output sequentially using the Read En-
able signal.
ings requirements.
Write Protect
Write Protect bus operations are used to protect
the memory against program or erase operations.
When the Write Protect signal is Low the device
will not accept program or erase operations and so
the contents of the memory array cannot be al-
tered. The Write Protect signal is not latched by
Write Enable to ensure protection even during
power-up.
Standby
When Chip Enable is High the memory enters
Standby mode, the device is deselected, outputs
are disabled and power consumption is reduced.
Table 5. Bus Operations
Note: 1. Only for x16 devices.
2. WP must be VIH when issuing a program or erase command.
Bus Operation
E
AL
CL
R
W
WP
I/O0 - I/O7
I/O8 - I/O15(1)
Command Input
VIL
VIH
Rising
X(2)
Command
X
Address Input
VIL
VIH
VIL
VIH
Rising
X
Address
X
Data Input
VIL
VIH
Rising
VIH
Data Input
Data Output
VIL
Falling
VIH
X
Data Output
Write Protect
X
VIL
XX
Standby
VIH
XX
X
VIL/VDD
XX