s29cd-j Meet Spansion Inc., s29cd-j Datasheet - Page 48

• Manufacturer Part Number: s29cd-j
• Description: 32/16 Megabit Cmos 2.6 Volt Or 3.3 Volt-only Simultaneous Read/write, Dual Boot, Burst Mode Flash Memory With Versatilei/o?
• Manufacturer: Meet Spansion Inc.

10.1
10.2
11. Electronic Marking
12. Power Conservation Modes
12.1
48
Secured Silicon Sector Protection Bit
Secured Silicon Sector Entry and Exit Commands
Standby Mode
The Secured Silicon Sector can be shipped unprotected, allowing customers to utilize that sector in any
manner they choose.
Please note the following:
The system can access the Secured Silicon Sector region by issuing the three-cycle Enter Secured Silicon
Sector command sequence. The device continues to access the Secured Silicon Sector region until the
system issues the four-cycle Exit Secured Silicon Sector command sequence. See the
Array Command Definitions (x32 Mode), on page 72
(x32 Mode), on page 73
The Secured Silicon Sector Entry Command allows the following commands to be executed
After the system has written the Enter Secured Silicon Sector command sequence, it can read the Secured
Silicon Sector by using the addresses listed in
This mode of operation continues until the system issues the Exit Secured Silicon Sector command
sequence, or until power is removed from the device.
Electronic marking has been programmed into the device, prior to shipment from Spansion, to ensure
traceability of individual products. The electronic marking is stored and locked within a one-time
programmable region. Detailed information on Electronic Marking will be provided in a datasheet supplement.
When the system is not reading or writing to the device, it can place the device in standby mode. In this mode,
current consumption is greatly reduced, and outputs are placed in a high impedance state, independent of
OE# input. The device enters CMOS standby mode when the CE# and RESET# inputs are both held at V
± 0.2 V. The device requires standard access time (t
device is deselected during erasure or programming, the device draws active current until the operation is
completed.
I
specification.
CC5
The Secured Silicon Sector can be read any number of times, but can be programmed and locked only
once. The Secured Silicon Sector Protection Bit must be used with caution as once locked, there is no
procedure available for unlocking the Secured Silicon Sector area and none of the bits in the Secured
Silicon Sector memory space can be modified in any way.
Once the Secured Silicon Sector is locked and verified, the system must write the Exit Secured Silicon
Sector Region command sequence to return the device to the memory array.
Read Secured Silicon areas
Program Secured Silicon Sector (only once)
in
Silicon sector if the overlayed sector was undergoing programming or erasure. The host system
must ensure that the device resume any suspended program or erase operation after exiting the
Secured Silicon sector.
Section 15.1, DC Characteristic, CMOS Compatible on page 51
for address and data requirements for both command sequences.
S29CD-J & S29CL-J Flash Family
D a t a
S h e e t
Table 10.1, Secured Silicon Sector Addresses on page
CE
and
( P r e l i m i n a r y )
) for read access before it is ready to read data. If the
Table 20.2, Sector Protection Command Definitions
represents the standby current
S29CD-J_CL-J_00_B2 March 7, 2007
Table 20.1, Memory
47.
CC