AM29LV320DT90EI AMD (ADVANCED MICRO DEVICES), AM29LV320DT90EI Datasheet - Page 33

• Manufacturer Part Number: AM29LV320DT90EI
• Description: Flash Memory IC
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of AM29LV320DT90EI

• Memory Configuration: 4M X 8 / 2M X 16 Bit
• Package/case: 48-TSOP
• Supply Voltage Max: 3.6V
• Leaded Process Compatible: No
• Peak Reflow Compatible (260 C): No
• Access Time, Tacc: 90nS
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

RY/BY#: Ready/Busy#
The RY/BY# is a dedicated, open-drain output pin
which indicates whether an Embedded Algorithm is in
progress or complete. The RY/BY# status is valid after
the rising edge of the final WE# pulse in the command
sequence. Since RY/BY# is an open-drain output, sev-
eral RY/BY# pins can be tied together in parallel with a
pull-up resistor to V
If the output is low (Busy), the device is actively eras-
ing or programming. (This includes programming in
the Erase Suspend mode.) If the output is high
(Ready), the device is in the read mode, the standby
mode, or in the erase-suspend-read mode. Table 15
on page 33 shows the outputs for RY/BY#.
DQ6: Toggle Bit I
Toggle Bit I on DQ6 indicates whether an Embedded
Program or Erase algorithm is in progress or com-
plete, or whether the device entered the Erase Sus-
pend mode. Toggle Bit I may be read at any address,
and is valid after the rising edge of the final WE# pulse
in the command sequence (prior to the program or
erase operation), and during the sector erase time-out.
During an Embedded Program or Erase algorithm op-
eration, successive read cycles to any address cause
DQ6 to toggle. The system may use either OE# or
CE# to control the read cycles. When the operation is
complete, DQ6 stops toggling.
After an erase command sequence is written, if all
sectors selected for erasing are protected, DQ6 tog-
gles for approximately 100 µs, then returns to reading
array data. If not all selected sectors are protected, the
Embedded Erase algorithm erases the unprotected
sectors, and ignores the selected sectors that are pro-
tected.
The system can use DQ6 and DQ2 together to deter-
mine whether a sector is actively erasing or is
erase-suspended. When the device is actively erasing
(that is, the Embedded Erase algorithm is in progress),
DQ6 toggles. When the device enters the Erase Sus-
pend mode, DQ6 stops toggling. However, the system
must also use DQ2 to determine which sectors are
erasing or erase-suspended. Alternatively, the system
can use DQ7 (see the subsection on “DQ7: Data#
Polling” on page 30).
If a program address falls within a protected sector,
DQ6 toggles for approximately 1 µs after the program
command sequence is written, then returns to reading
array data.
DQ6 also toggles during the erase-suspend-program
mode, and stops toggling once the Embedded Pro-
gram algorithm is complete.
Table 15 on page 33 shows the outputs for Toggle Bit I
on DQ6.
December 14, 2005
Figure 7, on page 31
CC
.
shows the toggle bit al-
D A T A S H E E T
Am29LV320D
gorithm.
tics” section shows the toggle bit timing diagrams.
Figure 22, on page 45
DQ2 and DQ6 in graphical form. See also the subsec-
tion on
DQ2: Toggle Bit II
The “Toggle Bit II” on DQ2, when used with DQ6, indi-
cates whether a particular sector is actively erasing
(that is, the Embedded Erase algorithm is in progress),
Note: The system should recheck the toggle bit even if DQ5
= “1” because the toggle bit may stop toggling as DQ5
changes to “1.” See the subsections on DQ6 and DQ2 for
more information.
No
DQ2: Toggle Bit
Figure 21, on page 45
Figure 7. Toggle Bit Algorithm
Complete, Write
Reset Command
Read DQ7–DQ0
Read DQ7–DQ0
Read DQ7–DQ0
Program/Erase
Operation Not
Toggle Bit
Toggle Bit
DQ5 = 1?
= Toggle?
= Toggle?
START
Twice
Yes
Yes
Yes
shows the differences between
II.
in the “AC Characteris-
Operation Complete
No
No
Program/Erase
31