R1EX24256BSAS0A_12 Datasheet, PDF (14/18 Pages) Renesas Technology Corp – Two-wire serial interface 256k EEPROM (32-kword 8-bit)

R1EX24256BSAS0A/R1EX24256BTAS0A
Notes
Data Protection at V_CC On/Off
When V_CC is turned on or off, noise on the SCL and SDA 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 has a power on reset function. Be careful of the notices described below in order for the power on reset
function to operate correctly.
 SCL and SDA should be fixed to V_CC or V_SS 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 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 rate should be slower than 2 s/V.
Noise Suppression Time
This EEPROM have a noise suppression function at SCL and SDA inputs, that cut noise of width less than 100 ns. Be
careful not to allow noise of width more than 100 ns.
R10DS0005EJ0101 Rev.1.01
Jul. 26, 2012
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