TPS65983B: PD sink No GOOD CRC return

Peiwu.Ren

Part Number: TPS65983B

Hi TI team:

In my application, the TPS65983 is configured in UFP mode, and TX sink capability is set as shown in the figure below:

In practical application, it is found that the chip does not send a PD sink request after connecting the PD source. We used the logic analyzer to grasp the PD negotiation process and found that after the PD source sent the source cap(5V,1.5A), the sink did not return the GOOD CRC.

As far as I understand, the source cap is sent only after the CC of the master-slave device is connected, so it can be proved that the CC signal is connected normally.

Therefore, I don't know what happened, which will cause tps65983 not to return GOOD CRC.

By the way, this error is a probability. It can also negotiate successfully

So, I need your technical support.

over 4 years ago

0 Jacob Ontiveros over 4 years ago

TI__Expert 6280 points

Hi,

The PD controller has integrated dead battery resistors that will create the pull up (DFP) and pull down (UFP) divider needed to detect a connection. Once this connection is detected the DFP will source VBUS and if it supports USB PD it will start to send the Source Capabilities.

With that being said, the issue can be that the FW on the PD controller was not successfully loaded or there is a HW issue prevent the PD controller from reading the SPI flash.

Please check the link below on the next debug steps:

https://e2e.ti.com/support/interface-group/interface/f/interface-forum/1005389/tps65983b-technical-question-for-pd-controller-tps65983bazbhr/3758748#3758748

Jacob

0 Peiwu.Ren over 4 years ago in reply to Jacob Ontiveros

Prodigy 180 points

In my design, the firmware of UFP is stored in region 1. Before connecting CC, the PD controller is controlled to load firmware from region 1 through I2C BUS. Therefore, it may be that PD controller did not load firmware successfully.

Is there any way to confirm whether FW is loaded successfully? A register? In this way, I can ensure that the CC signal is connected after the FW load is successful.

0 Jacob Ontiveros over 4 years ago in reply to Peiwu.Ren

TI__Expert 6280 points

Hi,

The PD controller will load the FW from the shared SPI flash with the TBT controller. The I2C interface is used to report the connection status to the TBT controller.

You can probe the SPI CLK to see if the PD Controller and TBT controller are accessing the SPI flash.

Did you merge the TBT and PD controller FW using Imaginarium? This will have to be programmed on the SPI flash.

Jacob

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TPS65983B: PD sink No GOOD CRC return