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R1EX24002ASAS0I_15 Datasheet, PDF (14/18 Pages) Renesas Technology Corp – Two-wire serial interface 2k EEPROM (256-word x 8-bit)
R1EX24002ASAS0I/R1EX24002ATAS0I
Notes
Data Protection at VCC On/Off
When VCC 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 VCC or VSS during VCC on/off. Low to high or high to low transition during VCC
on/off may cause the trigger for the unintentional programming.
• VCC should be turned off after the EEPROM is placed in a standby state.
• VCC should be turned on from the ground level(VSS) in order for the EEPROM not to enter the unintentional
programming mode.
• VCC turn on rate should be slower than 2 μs/V.
Noise Suppression Time
This EEPROM have a noise suppression function at SCL and SDA inputs, that cut noise of width less than 50 ns. Be
careful not to allow noise of width more than 50 ns.
Power Source Noise Countermeasures
In order to suppress power-source-noise which causes malfunction of the device, it is recommended to put 0.1μF
bypass-capacitor (such as a monolithic ceramic capacitor which has good high-frequency characteristics) between VCC
and VSS, and shorten the wiring length between the capacitor and VCC/VSS terminals as much as possible.
Device Address Input, Write Protect input
You can use this device with device-address and write-protect pins open state, because these pins are pulled down
inside of the device. However, we recommend you connect these pins to VCC or VSS to avoid malfunction due to noise.
R10DS0221EJ0200 Rev.2.00
Nov 07, 2013
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