lrs1830 Sharp Microelectronics of the Americas, lrs1830 Datasheet - Page 62

• Manufacturer Part Number: lrs1830
• Description: Stacked Chip 256m X16 Boot Block Flash And 32m X16 Scram
• Manufacturer: Sharp Microelectronics of the Americas

8. Flash Memory Data Protection
Noises having a level exceeding the limit specified in the specification may be generated under specific operating conditions on
some systems. Such noises, when induced onto WE signal or power supply, may be interpreted as false commands and causes
undesired memory updating. To protect the data stored in the flash memory against unwanted writing, systems operating with the
flash memory should have the following write protect designs, as appropriate:
The below describes data protection method.
Protection against noises on WE signal
1. Protection of data in each block
2. Protection of data with F-RST
sharp
•
• For detailed block locking scheme, see Section 6.2 Command Definitions for Flash Memory.
• Especially during power transitions such as power-up and power-down, the flash memory enters reset mode by bringing
• For detailed description on F-RST control, see Section 6.6.6 AC Electrical Characteristics for Flash Memory, Reset
To prevent the recognition of false commands as write commands, system designer should consider the method for
reducing noises on WE signal.
locked- down block by setting its block lock-down bit is protected from lock status changes.
By using this function, areas can be defined, for example, program area (locked blocks), and data area (unlocked
blocks).
F-RST to low, which inhibits write operation to all blocks.
Operations.
ny locked block by setting its block lock bit is protected against the data alternation. When WP/A
L R S1 8 3 0
CC
is low, any
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