AM50DL128BH Datasheet, PDF (22/68 Pages) Advanced Micro Devices – Stacked Multi-Chip Package (MCP) Flash Memory and SRAM

ADVANCE INFORMATION
If the system asserts V_IH on the WP#/ACC pin, the de-
vice reverts to whether sectors 0, 1, 140, and 141
were last set to be protected or unprotected. That is,
sector protection or unprotection for these sectors de-
pends on whether they were last protected or unpro-
tected using the method described in “Sector/Sector
Block Protection and Unprotection”.
Note that the WP#/ACC pin must not be left floating or
unconnected; inconsistent behavior of the device may
result.
Table 7. WP#/ACC Modes
WP# Input
Voltage
V_IL
V_IH
V_HH
Device
Mode
Disables programming and erasing in
SA0, SA1, SA140, and SA141
Enables programming and erasing in
SA0, SA1, SA140, and SA141
Enables accelerated progamming (ACC).
See “Accelerated Program Operation” on
page 13.
Temporary Sector Unprotect
(Note: For the following discussion, the term “sector”
applies to both sectors and sector blocks. A sector
block consists of two or more adjacent sectors that are
protected or unprotected at the same time (see Table
6).
This feature allows temporary unprotection of previ-
ously protected sectors to change data in-system. The
Sector Unprotect mode is activated by setting the RE-
SET# pin to VID. During this mode, formerly protected
sectors can be programmed or erased by selecting the
sector addresses. Once V_ID is removed from the RE-
SET# pin, all the previously protected sectors are
protected again. Figure 1 shows the algorithm, and
Figure 26 shows the timing diagrams, for this feature.
If the WP#/ACC pin is at V_IL, sectors 0, 1, 140, and
141 will remain protected during the Temporary sector
Unprotect mode.
START
RESET# = V_ID
(Note 1)
Perform Erase or
Program Operations
RESET# = V_IH
Temporary Sector
Unprotect Completed
(Note 2)
Notes:
1. All protected sectors unprotected (If WP#/ACC = V_IL,
sectors 0, 1, 140, and 141 will remain protected).
2. All previously protected sectors are protected once
again.
Figure 1. Temporary Sector Unprotect Operation
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Am50DL128BH
October 7, 2003