Other Parts Discussed in Thread: TPS65988
Hello,
We have a design for a USB-C connector with DisplayPort Alt mode. We use the TUSB1046A-DCI redriver with a TPS65988 power delivery IC. In this case, our design is the DFP and we are trying to send a video signal to a USB-C display.
When we connect the display using the USB-C cable, it is detected by the TPS65988 IC and it sends power to the display as expected. Also, the TPS65988 controls the TUSB1046 using the GPIO control mode.
In our Linux device, we can detect the display (resolution, FPS, dimensions) which suggests that the AUX channel works properly. However, the display never receives a video signal so no image is displayed.
The Linux device sends its video output on a single lane DisplayPort signal that is fed to the TUSB1046A-DCI. The CTL pins of the TUSB1046 are set at CTL0 = 0 and CTL1 = 1. According to table 4 of the datasheet, all 4 DisplayPort lanes should be sent on the USB-C connector in this configuration. https://www.ti.com/lit/ds/symlink/tusb1046a-dci.pdf?ts=1629894150520. However, there is still no image on the display.
Our single lane DisplayPort signal is fed to the DP3 input of the TUSB1046 IC. I suspect this might be the issue. In a single lane application, does the DisplayPort signal absolutely needs to be on the DP0 lane?
If needed, I can provide the schematics in a direct message.
Thanks
