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CDCEL937 / serial programming interface

Other Parts Discussed in Thread: CDCEL937


We are trying to program CDCEL937. Please let me know how to set I2C master mode(EEPROM) and I2C slave mode.

In addition, if we use only I2C pin mode, not set as control pin mode, may VDDOUT be forced  to GND sometime ?

Best Regards,


  • Kato-san,

    the CDCEL937 does not have a I2C master mode. It can only operate in Slave mode.
    If you want to use the internal EEPROM, you will need to program the register setting once. Afterwards, writing a '1' to EEWRITE (Offset 06h bit 0) will initiate the Register to EEPROM write.
    As soon the write is completed (EEPIP=0), the CDCEL937 start with your configuration after every power up.

    please refer to datasheet page 16.

    VDDOUT is an input and can be forced to GND ONLY externally.

    best regards,