TINY12 ATMEL [ATMEL Corporation], TINY12 Datasheet - Page 40

• Manufacturer Part Number: TINY12
• Description: 8-bit AVR Microcontroller with 1K Byte Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Prevent EEPROM
Corruption
40
ATtiny11/12
During periods of low V
age is too low for the CPU and the EEPROM to operate properly. These issues are the
same as for board-level systems using the EEPROM, and the same design solutions
should be applied.
An EEPROM data corruption can be caused by two situations when the voltage is too
low. First, a regular write sequence to the EEPROM requires a minimum voltage to
operate correctly. Secondly, the CPU itself can execute instructions incorrectly if the
supply voltage for executing instructions is too low.
EEPROM data corruption can easily be avoided by following these design recommen-
dations (one is sufficient):
1. Keep the AVR RESET active (low) during periods of insufficient power supply
2. Keep the AVR core in Power-down Sleep Mode during periods of low V
3. Store constants in Flash memory if the ability to change memory contents from
voltage. This can be done by enabling the internal Brown-out Detector (BOD) if
the operating speed matches the detection level. If not, an external low V
Reset Protection circuit can be applied.
will prevent the CPU from attempting to decode and execute instructions, effec-
tively protecting the EEPROM registers from unintentional writes.
software is not required. Flash memory can not be updated by the CPU, and will
not be subject to corruption.
CC
, the EEPROM data can be corrupted because the supply volt-
1006D–AVR–07/03
CC
CC
. This