M29W320EB NUMONYX [Numonyx B.V], M29W320EB Datasheet - Page 14

• Manufacturer Part Number: M29W320EB
• Description: 32 Mbit (4Mbx8 or 2Mbx16, Uniform Parameter Blocks, Boot Block) 3V supply Flash memory
• Manufacturer: NUMONYX [Numonyx B.V]

Signal descriptions
2.7
2.8
2.9
14/63
Write Enable (W)
The Write Enable, W, controls the Bus Write operation of the memory’s Command interface.
V
The V
use an external high voltage power supply to reduce the time required for Program
operations. This is achieved by bypassing the unlock cycles and/or using the Double word or
Quadruple byte Program commands.
The Write Protect function provides a hardware method of protecting the two outermost boot
blocks. When V
blocks; Program and Erase operations in these blocks are ignored while V
Low, even when RP is at V
When V
of the two outermost boot blocks. Program and Erase operations can now modify the data
in these blocks unless the blocks are protected using Block Protection.
When V
Bypass mode. When V
During Unlock Bypass Program operations the memory draws I
programming circuits. See the description of the Unlock Bypass command in the Command
interface section. The transitions from V
t
Never raise V
memory may be left in an indeterminate state.
The V
become unreliable. A 0.1µF capacitor should be connected between the V
pin and the V
track widths must be sufficient to carry the currents required during Unlock Bypass Program,
I
Reset/Block Temporary Unprotect (RP)
The Reset/Block Temporary Unprotect pin can be used to apply a Hardware Reset to the
memory or to temporarily unprotect all Blocks that have been protected.
Note that if V
if RP is at V
A Hardware Reset is achieved by holding Reset/Block Temporary Unprotect Low, V
least t
ready for Bus Read and Bus Write operations after t
See the Ready/Busy Output section,
Unprotect ac
Holding RP at V
and Erase operations on all blocks will be possible. The transition from V
slower than t
VHVPP
PP
PP/
.
PP
PP
PLPX
Write Protect (V
, see
PP
PP
/Write Protect pin provides two functions. The V
/Write Protect pin must not be left floating or unconnected or the device may
/Write Protect is High, V
/Write Protect is raised to V
. After Reset/Block Temporary Unprotect goes High, V
ID
Figure 16
PHPHH
PP
SS
.
waveforms, for more details.
PP
/WP is at V
PP
/Write Protect to V
ID
Ground pin to decouple the current surges from the power supply. The PCB
/Write Protect is Low, V
will temporarily unprotect the protected Blocks in the memory. Program
.
PP
/Write Protect returns to V
IL
ID
, then the two outermost boot blocks will remain protected even
.
PP
/WP)
PP
IH
, the memory reverts to the previous protection status
Table 16
from any mode except Read mode, otherwise the
PP
IH
the memory automatically enters the Unlock
IL
to V
, the memory protects the two outermost boot
PP
and
and from V
Figure 15: Reset/Block Temporary
IH
PHEL
or V
PP
or t
IL
function allows the memory to
normal operation resumes.
PP
RHEL
PP
to V
M29W320ET, M29W320EB
IH
, whichever occurs last.
from the pin to supply the
, the memory will be
IH
must be slower than
IH
PP
PP
to V
/Write Protect is
/Write Protect
ID
must be
IL
, for at