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TCA9534: Cannot detect TCA9534 by I2c

Part Number: TCA9534
Other Parts Discussed in Thread: TCA6408A,

Hi team,

My customer is using our TCA9534 at their new design since  the shortage of TCA6408A, and have the problem that we cannot detect TCA9534 via I2C .

According to their previous experience on TCA6424ARGJR or others, there is reset pin to solve the issue, but  there is no reset input on TCA9534..

Please refer the schematic as below. Do you have any suggestion for analysis? Thank for your kindly help.

  • In the schematic shown, the TCA9534 is configured for a different address. Was the software adjusted for that?

  • Hello, 

    The device is still able to be reset without a RESET pin. It has a power-on reset feature that can be used to reset the device to default conditions in the case of a glitch or data corruption. If there is a need to reset the device, this feature can be used for that purpose.

    As mentioned by Clemens, the TCA9534 will not respond to a controller if the wrong target address is being sent over the I2C bus. The address being sent from the controller to the target should match the configured address of the target device. This device has hardware addressable target address bits (A2-A0) that allow the user to change the target address of the device by either connecting them to VCC or GND. Could you please provide an oscilloscope screenshot of an I2C communication frame with the device so that we can verify that the correct target address is being sent by the controller?  

    Best, 

    Kenneth