M29W160ET, M29W160EB
10/40
SIGNAL DESCRIPTIONS
See Figure 2, L ogic Diag ram, and T able 1, Sign al
Names, for a brief overview of the s ignals connect-
ed to this d evice .
Address Inputs (A0-A19). The Address Inputs
sele ct the cell s in the memory a rray to access d ur-
ing Bus Read operations. During Bus Wri te opera-
tions they control the commands sent to the
Command Interface of the Program/Erase Con-
troller.
Data Inputs/Outputs (DQ0-DQ7). The Data In-
puts/Outputs out put the data stored at the selected
address during a Bus Read operation. Duri ng Bus
Write operations they represent the commands
sent to the Command Interface of the Program/
Erase Controller.
Data Inputs/Outputs (DQ8-DQ14). The Data In-
puts/Outputs out put the data stored at the selected
address during a Bus Read operati on when BYTE
is High, VIH. When BYTE is Low, VIL, these pins
are not used and are high impedance. During Bus
Write operations the Command Register does not
use these bits . When reading t he Status Register
these bits should be ignored.
Data Input/Output or Address Input (DQ15A-1).
When BYTE is High, VIH, this pin behaves as a
Data Input/Output pin (as DQ8-DQ14). When
BYTE is Low, VIL, t his pin beh aves as an address
pin; DQ15A–1 Low will select t he LSB of the Word
on the other addresses, DQ15A–1 Hi gh will select
the MSB . Throughout the text consider references
to the Data Input/Output to include this pin when
BYTE is High and references to the Address In-
puts to inclu de this pin when BYT E is Low except
when stated explicitly otherwise.
Chip Enable (E). The Chip Enable, E, activates
the memor y, allowing Bus Read and Bus Write op-
erations to be performed. When Chip Enable is
High, VIH, all other pins are ignored.
Output Enable (G). The Output Enable, G, con-
trols the B us Read operat ion of the memory.
Write Enable (W). T he Write Enable, W, controls
the Bus Write operation of the memory’s Com-
ma nd Inte r face.
Reset/Block Temporary Unprotect ( RP). The
Reset/Block Temporary Unprotect pin can be
used to apply a Hardware Reset to t he memory or
to temporarily unprot ect al l Blocks that have b een
protected.
A Hardware Reset is achieved by holding Reset/
Block Temporary Unprotect Low, VIL, for at least
tPLPX. After Reset/Block Temporary Unprotect
goes High, V IH, the memory will be ready for Bus
Read and Bus Write operations after tPHEL or
tRHEL, whichever occurs last. See the Ready/ Busy
Output section, Table 15 and Figure 14, Reset/
Temporary Unprot ect AC Charact eris tics for more
details.
Holding RP at VID will temporarily unprotect the
protected Blocks in the memory. Program and
Erase operations on all blocks will be possible.
The transition from VIH to VID must be sl ower than
tPHPHH.
Ready/Busy Output (RB). The Ready/Busy pin
is an open-drain output that can be used to identify
when the device is performing a P rogr am or Erase
operation. During Program or Erase operations
Ready/Busy is Low, V OL. Read y/Busy is high-im-
pedance during Read mode, Auto Select mode
and Erase Suspend m ode.
After a Hardware Reset, Bus Read and Bus Write
operations cannot begin until Ready/Busy be-
comes h igh-impeda nc e. See Tabl e 15 a nd Fi gure
14, Reset/Temporary Unprotect AC Characteris-
tics.
The use of an open-drain output allows t he Ready/
Busy pins from several memories to be connected
to a single pull-up resistor. A Low will then i ndicate
that one, or more, of the me mories is busy.
Byte/Word Organization Select (BYTE). The
Byte/Word Organization Select pin is used to
switch bet ween the 8-bit and 16-bit Bus m odes of
the memory. When Byte/Word Organization Se-
lect is Low, VIL, the memory is in 8-bit mode, when
it is Hig h, VIH, the memory is in 16-bit mode.
VCC Supply Voltage. The VCC Supply Voltage
supplies the power for all operations (Read, Pro-
gram, Erase etc.).
The Command Interface is disabl ed when the VCC
Supply Voltage is less than the Lockout Voltage,
VLKO. This prevents Bus Write operations from ac-
cidentally damaging the data during power up,
power down and power surges. If the Program/
Erase Controller is programming or erasing during
this time then the operation aborts and t he memo-
ry contents being altered wi ll be invalid.
A 0.1µF capacitor should be connected between
the V CC Supply Voltage pin and the VSS Ground
pin to decoupl e the current surges from the power
supply. The PCB track widths must be sufficient to
carry the currents required during program and
erase operat ions, ICC3.
VSS Ground. The VSS Ground is the referenc e for
all v ol tage measurements. T he two VSS pins of the
device m ust be connected to the system ground.