STA369BWS STMicroelectronics, STA369BWS Datasheet - Page 28

• Manufacturer Part Number: STA369BWS
• Description: Multimedia Misc 2.1-channel 40-watt High-EFF Dig Audio
• Manufacturer: STMicroelectronics

Specifications of STA369BWS

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7.13
7.14
8. Secured Silicon Sector Flash Memory Region
26
Write Protect (WP#) — Models 03, 04 Only
Temporary Sector Unprotect
The Write Protect function provides a hardware method of protecting certain boot sectors without using V
This function is one of two provided by the WP#/ACC pin.
If the system asserts V
outermost 8-Kbyte boot sectors independently of whether those sectors were protected or unprotected using
the method described in
sectors are the two sectors containing the lowest addresses in a bottom-boot-configured device, or the two
sectors containing the highest addresses in a top-boot-configured device.
If the system asserts V
sectors were last set to be protected or unprotected. That is, sector protection or unprotection for these two
sectors depends on whether they were last protected or unprotected using the method described in
Protection/Unprotection on page
Note that the WP#/ACC pin must not be left floating or unconnected; inconsistent behavior of the device may
result.
This feature allows temporary unprotection of previously protected sectors to change data in-system. The
Sector Unprotect mode is activated by setting the RESET# pin to V
sectors can be programmed or erased by selecting the sector addresses. Once V
RESET# pin, all the previously protected sectors are protected again. shows the algorithm, and
on page 56
Notes
1. All protected sectors unprotected.
2. All previously protected sectors are protected once again.
The Secured Silicon Sector feature provides a 256-byte Flash memory region that enables permanent part
identification through an Electronic Serial Number (ESN). The Secured Silicon Sector uses a Secured Silicon
Sector Indicator Bit (DQ7) to indicate whether or not the Secured Silicon Sector is locked when shipped from
the factory. This bit is permanently set at the factory and cannot be changed, which prevents cloning of a
factory-locked part. This ensures the security of the ESN once the product is shipped to the field.
Spansion offers the device with the Secured Silicon Sector either factory-locked or customer-lockable. The
factory-locked version is always protected when shipped from the factory, and has the Secured Silicon Sector
shows the timing diagrams, for this feature.
IH
IL
on the WP#/ACC pin, the device disables program and erase functions in the two
on the WP#/ACC pin, the device reverts to whether the two outermost 8-KByte boot
Sector Protection/Unprotection on page
Figure 7.2 Temporary Sector Unprotect Operation
22.
S29AL032D
Unprotect Completed
Program Operations
Temporary Sector
D a t a
Perform Erase or
RESET# = V
RESET# = V
(Note 1)
(Note 2)
START
S h e e t
ID
IH
22. The two outermost 8-Kbyte boot
ID
. During this mode, formerly protected
S29AL032D_00_A9 January 19, 2007
ID
is removed from the
Figure 17.11
Sector
ID
.