Datasheet

2 Mbit / 4 Mbit / 8 Mbit Multi-Purpose Flash

SST39LF200A / SST39LF400A / SST39LF800A

SST39VF200A / SST39VF400A / SST39VF800A

Data Sheet

Microchip Technology Company

Hardware Data Protection

Noise/Glitch Protection: A WE# or CE# pulse of less than 5 ns will not initiate a write cycle.

Power Up/Down Detection: The Write operation is inhibited when V

is less than 1.5V.

Write Inhibit Mode: Forcing OE# low, CE# high, or WE# high will inhibit the Write operation. This pre-

vents inadvertent writes during power-up or power-down.

Software Data Protection (SDP)

The SST39LF200A/400A/800A and SST39VF200A/400A/800A provide the JEDEC approved Soft-

ware Data Protection scheme for all data alteration operations, i.e., Program and Erase. Any Program

operation requires the inclusion of the three-byte sequence. The three-byte load sequence is used to

initiate the Program operation, providing optimal protection from inadvertent Write operations, e.g.,

during the system power-up or power-down. Any Erase operation requires the inclusion of six-byte

sequence. This group of devices are shipped with the Software Data Protection permanently enabled.

See Table 4 for the specific software command codes. During SDP command sequence, invalid com-

mands will abort the device to Read mode within TRC. The contents of DQ

-DQ

can be V

or V

but no other value, during any SDP command sequence.

Common Flash Memory Interface (CFI)

The SST39LF200A/400A/800A and SST39VF200A/400A/800A also contain the CFI information to

describe the characteristics of the device. In order to enter the CFI Query mode, the system must write

three-byte sequence, same as Software ID Entry command with 98H (CFI Query command) to

address 5555H in the last byte sequence. Once the device enters the CFI Query mode, the system

can read CFI data at the addresses given in Tables 5 through 9. The system must write the CFI Exit

command to return to Read mode from the CFI Query mode.

Product Identification

The Product Identification mode identifies the devices as the SST39LF/VF200A, SST39LF/VF400A

and SST39LF/VF800A and manufacturer as SST. This mode may be accessed by software operations.

Users may use the Software Product Identification operation to identify the part (i.e., using the device

ID) when using multiple manufacturers in the same socket. For details, see Table 4 for software opera-

tion, Figure 13 for the Software ID Entry and Read timing diagram, and Figure 20 for the Software ID

Entry command sequence flowchart.

Table 2: Product Identification

Address Data

Manufacturer’s ID 0000H 00BFH

Device ID

SST39LF/VF200A 0001H 2789H

SST39LF/VF400A 0001H 2780H

SST39LF/VF800A 0001H 2781H

T2.3 25001