S70GL01GN00 Datasheet, PDF (32/83 Pages) SPANSION – 3.0 Volt-only Page Mode Flash Memory featuring 110 nm MirrorBit™ Process Technology

Advance Information
without utilizing the Write Buffer of the device. During a Lock Register program-
ming sequence execution, the DQ6 Toggle Bit I toggles until the programming of
the Lock Register is completed which indicates programming status. All Lock Reg-
ister bits are readable to allow users to verify Lock Register statuses.
The Customer Secured Silicon Sector Protection Bit is DQ0, Persistent Protection
Mode Lock Bit is DQ1, and Password Protection Mode Lock Bit is DQ2 are acces-
sible by all users. Each of these bits are non-volatile. DQ15-DQ3 are reserved and
must be 1's when the user tries to program the DQ2, DQ1, and DQ0 bits of the
Lock Register. The user is not required to program DQ2, DQ1 and DQ0 bits of the
Lock Register at the same time. This allows users to lock the Secured Silicon Sec-
tor and then set the device either permanently into Password Protection Mode or
Persistent Protection Mode and then lock the Secured Silicon Sector at separate
instances and time frames.
„ Secured Silicon Sector Protection allows the user to lock the Secured Silicon
Sector area
„ Persistent Protection Mode Lock Bit allows the user to set the device perma-
nently to operate in the Persistent Protection Mode
„ Password Protection Mode Lock Bit allows the user to set the device perma-
nently to operate in the Password Protection Mode
DQ15-3
Don’t Care
Table 4. Lock Register
DQ2
DQ1
DQ0
Password Protection
Mode Lock Bit
Persistent Protection
Secured Silicon
Mode Lock Bit
Sector Protection Bit
Persistent Sector Protection
The Persistent Sector Protection method replaces the old 12 V controlled protec-
tion method while at the same time enhancing flexibility by providing three
different sector protection states:
„ Dynamically Locked—The sector is protected and can be changed by a sim-
ple command
„ Persistently Locked—A sector is protected and cannot be changed
„ Unlocked—The sector is unprotected and can be changed by a simple com-
mand
In order to achieve these states, three types of bits are going to be used:
Dynamic Protection Bit (DYB)
A volatile protection bit is assigned for each sector. After power-up or hardware
reset, the contents of all DYB bits are in the unprotected state. Each DYB is indi-
vidually modifiable through the DYB Set Command and DYB Clear Command.
When the parts are first shipped, all of the Persistent Protect Bits (PPB) are
cleared into the unprotected state. The DYB bits and PPB Lock bit are defaulted
to power up in the cleared state or unprotected state - meaning the all PPB bits
are changeable.
The Protection State for each sector is determined by the logical OR of the PPB
and the DYB related to that sector. For the sectors that have the PPB bits cleared,
the DYB bits control whether or not the sector is protected or unprotected. By is-
suing the DYB Set and DYB Clear command sequences, the DYB bits is protected
or unprotected, thus placing each sector in the protected or unprotected state.
These are the so-called Dynamic Locked or Unlocked states. They are called dy-
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S70GL01GN00 MirrorBit^TM Flash
S70GL01GN00_00_A1 June 1, 2005