Hi Team,
Good day!!
We are using the MP4255GVE-0000-Z as the DC/DC converter and the MP5031GRE-00A3-P as the USB-PD controller. Our design is based on the configuration shown in Figure 24: MP4255 and MP5031 Dual-Port 100W Shared PD Application.
The issue we are facing is that the MP5031 does not appear to be communicating with the MP4255. The USB output voltage remains fixed at the voltage configured on the MP4255, and we do not observe any communication or control activity between the MP5031 and MP4255.
We have attached the schematic for reference.
Our expectation is that when a USB-PD device is connected, the MP5031 should negotiate the required voltage and current and actively control the MP4255 to adjust the VBUS output accordingly. However, the output voltage remains constant regardless of the connected device.
Could you please help us identify whether there are any specific signals, register settings, or hardware connections that should be verified to ensure proper communication between the MP5031 and MP4255?
Thank you.
