2 Mbit / 4 Mbit / 8 Mbit Multi-Purpose Flash
SST39LF200A / SST39LF400A / SST39LF800A
SST39VF200A / SST39VF400A / SST39VF800A
Data Sheet
To meet surface mount requirements, the SST39LF200A/
400A/800A and SST39VF200A/400A/800A are offered in
48-lead TSOP packages and 48-ball TFBGA packages as
well as Micro-Packages. See Figures 2, 3, and 4 for pin
assignments.
Sector/Block-Erase Operation
The Sector- (or Block-) Erase operation allows the system
to erase the device on a sector-by-sector (or block-by-
block) basis. The SST39LF200A/400A/800A and
SST39VF200A/400A/800A offers both Sector-Erase and
Block-Erase mode. The sector architecture is based on
uniform sector size of 2 KWord. The Block-Erase mode is
based on uniform block size of 32 KWord. The Sector-
Erase operation is initiated by executing a six-byte com-
mand sequence with Sector-Erase command (30H) and
sector address (SA) in the last bus cycle. The Block-Erase
operation is initiated by executing a six-byte command
sequence with Block-Erase command (50H) and block
address (BA) in the last bus cycle. The sector or block
address is latched on the falling edge of the sixth WE#
pulse, while the command (30H or 50H) is latched on the
rising edge of the sixth WE# pulse. The internal Erase
operation begins after the sixth WE# pulse. The End-of-
Erase operation can be determined using either Data#
Polling or Toggle Bit methods. See Figures 11 and 12 for
timing waveforms. Any commands issued during the Sec-
tor- or Block-Erase operation are ignored.
Device Operation
Commands are used to initiate the memory operation func-
tions of the device. Commands are written to the device
using standard microprocessor write sequences. A com-
mand is written by asserting WE# low while keeping CE#
low. The address bus is latched on the falling edge of WE#
or CE#, whichever occurs last. The data bus is latched on
the rising edge of WE# or CE#, whichever occurs first.
Read
The Read operation of the SST39LF200A/400A/800A and
SST39VF200A/400A/800A is controlled by CE# and OE#,
both have to be low for the system to obtain data from the
outputs. CE# is used for device selection. When CE# is
high, the chip is deselected and only standby power is con-
sumed. OE# is the output control and is used to gate data
from the output pins. The data bus is in high impedance
state when either CE# or OE# is high. Refer to the Read
cycle timing diagram for further details (Figure 5).
Chip-Erase Operation
The SST39LF200A/400A/800A and SST39VF200A/400A/
800A provide a Chip-Erase operation, which allows the
user to erase the entire memory array to the “1” state. This
is useful when the entire device must be quickly erased.
The Chip-Erase operation is initiated by executing a six-
byte command sequence with Chip-Erase command (10H)
at address 5555H in the last byte sequence. The Erase
operation begins with the rising edge of the sixth WE# or
CE#, whichever occurs first. During the Erase operation,
the only valid read is Toggle Bit or Data# Polling. See Table
4 for the command sequence, Figure 10 for timing diagram,
and Figure 21 for the flowchart. Any commands issued dur-
ing the Chip-Erase operation are ignored.
Word-Program Operation
The SST39LF200A/400A/800A and SST39VF200A/400A/
800A are programmed on a word-by-word basis. Before
programming, the sector where the word exists must be
fully erased. The Program operation is accomplished in
three steps. The first step is the three-byte load sequence
for Software Data Protection. The second step is to load
word address and word data. During the Word-Program
operation, the addresses are latched on the falling edge of
either CE# or WE#, whichever occurs last. The data is
latched on the rising edge of either CE# or WE#, whichever
occurs first. The third step is the internal Program operation
which is initiated after the rising edge of the fourth WE# or
CE#, whichever occurs first. The Program operation, once
initiated, will be completed within 20 µs. See Figures 6 and
7 for WE# and CE# controlled Program operation timing
diagrams and Figure 18 for flowcharts. During the Program
operation, the only valid reads are Data# Polling and Tog-
gle Bit. During the internal Program operation, the host is
free to perform additional tasks. Any commands issued
during the internal Program operation are ignored.
Write Operation Status Detection
The SST39LF200A/400A/800A and SST39VF200A/400A/
800A provide two software means to detect the completion
of a write (Program or Erase) cycle, in order to optimize the
system write cycle time. The software detection includes
two status bits: Data# Polling (DQ
7
) and Toggle Bit (DQ
6
).
The End-of-Write detection mode is enabled after the rising
edge of WE#, which initiates the internal Program or Erase
operation.
©2007 Silicon Storage Technology, Inc.
S71117-09-000
2/07
2
SST [ SILICON STORAGE TECHNOLOGY, INC ]
