HN58X2508I Datasheet, PDF (25/29 Pages) Renesas Technology Corp – Electrically Erasable and Programmable Read Only Memory

HN58X2508I/HN58X2516I
Notes
Data Protection at V_CC On/Off
When V_CC is turned on or off, noise on S inputs generated by external circuits (CPU, etc) may act as a trigger
and turn the EEPROM to unintentional program mode. To prevent this unintentional programming, this
EEPROM have a power on reset function. Be careful of the notices described below in order for the power
on reset function to operate correctly.
• S should be fixed to V_CC during V_CC on/off. Low to high or high to low transition during V_CC on/off
may cause the trigger for the unintentional programming.
• V_CC should be turned on/off after the EEPROM is placed in a standby state.
• V_CC should be turned on from the ground level (V_SS) in order for the EEPROM not to enter the
unintentional programming mode.
• V_CC turn on speed should be slower than 10 µs/V.
• When WRSR or WRITE instruction is executed before V_CC turns off, V_CC should be turned off after
waiting write cycle time (t_W).
Rev.2.00, Aug.19.2004, page 25 of 27