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TUSB1046A-DCI: I2C mode/ GPIO mode

Part Number: TUSB1046A-DCI

Hi , 

We are using TUSB1046A-DCI one of our project for USB Host and DP port  Source ALT MUX


  1. USB DFP (Source side)
  2. USB3.1 + 2Lane DP
  3. GPIO Mode - I2C_EN( Pin 17 - Low)
  4. CTL0 (Pin 22 - High (3.3V))
  5. CTL1 (Pin 23 - High (3.3V))
  6. FLIP (Pin 21) - connected to Processor GPIO (GPIO Number #64) for Switching 
  7. We have separate PD for reading CC pins 


  1. When I Connected the Type C USB Hub to Our Device
  2. From PD Controller We identified CC1 is connected and USB is enumerated (read from I2C) 
  3. based on CC value we are toggling the Flip(Pin 21) for switching USB and DP lanes
  4. But MUX function is Not working

Issues/ Quires 

  1. In GPIO Mode CTL0/1 is presently connected to high only we are toggling flip signal, why it is not working
  2. We are tried to change I2C mode (I2C_EN( Pin 17 - High)) I2C bus is not working (Other devices in the same I2C bus is also not working looks like I2C bus failed when i connected i2c bus to TUSB1046A
  3. what are conditions needs to be check in GPIO mode and I2C modes
  4. Attached Schematic PDF for your reference - please review and let me know your comments 
  5. Same chip DP port also Not working Show error: