RC28F256P30B85 Micron Technology Inc, RC28F256P30B85 Datasheet - Page 37

• Manufacturer Part Number: RC28F256P30B85
• Manufacturer: Micron Technology Inc

Specifications of RC28F256P30B85

• Cell Type: NOR
• Density: 256Mb
• Access Time (max): 85/17ns
• Interface Type: Parallel/Serial
• Boot Type: Bottom
• Address Bus: 24b
• Operating Supply Voltage (typ): 1.8V
• Operating Temp Range: -40C to 85C
• Package Type: EZBGA
• Program/erase Volt (typ): 1.7 to 2/8.5 to 9.5V
• Sync/async: Async/Sync
• Operating Temperature Classification: Industrial
• Operating Supply Voltage (min): 1.7V
• Operating Supply Voltage (max): 2V
• Word Size: 16b
• Number Of Words: 16M
• Supply Current: 28mA
• Mounting: Surface Mount
• Pin Count: 64
• Lead Free Status / Rohs Status: Not Compliant

P30
10.0
10.1
10.1.1
10.1.2
10.1.3
August 2008
Order Number: 306666-12
Security Modes
The device features security modes used to protect the information stored in the flash
memory array. The following sections describe each security mode in detail.
Block Locking
Individual instant block locking is used to protect user code and/or data within the flash
memory array. All blocks power up in a locked state to protect array data from being
altered during power transitions. Any block can be locked or unlocked with no latency.
Locked blocks cannot be programmed or erased; they can only be read.
Software-controlled security is implemented using the Block Lock and Block Unlock
commands. Hardware-controlled security can be implemented using the Block Lock-
Down command along with asserting WP#. Also, V
inhibit program and erase operations (see
page 34
The P30 device also offers four pre-defined areas in the main array that can be
configured as One-Time Programmable (OTP) for the highest level of security. These
include the four 32 KB parameter blocks together as one and the three adjacent 128 KB
main blocks. This is available for top or bottom parameter devices.
Lock Block
To lock a block, issue the Lock Block Setup command. The next command must be the Lock Block command
issued to the desired block’s address (see
“Block Lock Operations Flowchart” on page
command is issued after the Block Lock Setup command, the device configures the RCR
instead.
Block lock and unlock operations are not affected by the voltage level on V
lock bits may be modified and/or read even if V
Unlock Block
The Unlock Block command is used to unlock blocks (see
on page
return to a locked state when the device is reset or powered down. If a block is in a
lock-down state, WP# must be deasserted before it can be unlocked (see
“Block Locking State Diagram” on page
Lock-Down Block
A locked or unlocked block can be locked-down by writing the Lock-Down Block
command sequence (see
down state cannot be programmed or erased; they can only be read. However, unlike
locked blocks, their locked state cannot be changed by software commands alone. A
locked-down block can only be unlocked by issuing the Unlock Block command with
WP# deasserted. To return an unlocked block to locked-down state, a Lock-Down
command must be issued prior to changing WP# to V
the locked state upon reset or power up the device (see
Diagram” on page
24). Unlocked blocks can be read, programmed, and erased. Unlocked blocks
and
Section 9.4, “Erase Protection” on page
38).
Section 6.0, “Command Set” on page
Section 6.0, “Command Set” on page 24
38).
Section 8.7, “Program Protection” on
86). If the Set Read Configuration Register
PP
is at or below V
PP
data security can be used to
36).
IL
. Locked-down blocks revert to
Figure 12, “Block Locking State
Section 6.0, “Command Set”
24). Blocks in a lock-
PPLK
.
and
Figure 12,
PP
. The block
Figure 40,
Datasheet
37