the USB2.0 DP1 and DN1 in USB-C connector does not work

[beyuc_3712261]

Hi,

I programmed a CYPD3125-40LQXI  with the hex code from a reference project "CYPD3125-40LQXI_notebook", then powered my project board with an external 5v and 3v power supply. The VBUS power is not used in the project board.

The project board has the CYPD3125 and a USB hub circuit.  The USB hub's upstream port is connected to the USB2.0 DP1 and DN1 in the USB-C connector.

Then I connect the USB-C connector in the project board to a laptop computer's USB-C connector, I found the USB hub is not working correctly (but looks like receiving signals from the laptop as the USB hub's LED  keeps flashing) . I also found the VBUS_P_CTRL0 and VBUS_P_CTRL1 changed output voltage from 3.6v to 4.4v.

I checked the USB hub circuit by connecting the USB hub's upstream port to a USB A port in a desk top computer. It works perfectly.

Please advise why the firmware of the reference project does not work.

Thanks,

Derong  Yuan

[ShifangZ_26]

Hi Derong,

1. Have you assured that the DP1&DP2 have connected to the USB 2.0 US DP? And DN1 &DN2 have connected to the USB2.0 US DN?

2. This test case, if you are source only, which is means you are DFP at initial states. Have you been initial DR_SWAP with this case?

3. VBUS_P_CTRL0 and VBUS_P_CTRL1 's voltage is relay on VBUS_P voltage. For N MOS FET. The charge-pump block is used to

boost the input VBUS to provide a higher voltage (VBUS +2*VDDD) on the NGDO_OUT output.

Best Regards,

Lisa

[beyuc_3712261]

Hi Lisa,

I think the chip is working. When  it is connected to a USB-C connector of a laptop a message "USB Root Hub (USB3.0)" is shown in the laptop's setup window but the USB hub's LED keeps flashing and the laptop can not detect anything plugged in the hub's downstream ports. When it is unplugged from the laptop the message is gone.

Here I have a question on programming the CYPD. Before programming I connected (by a wire) the Pin 1 of the SWD connector to VDDIO and VDDD and I set the programmer's 3.3v to power the chip while programming and I found the programming succeeded. But later when I tried to program again an error message is  shown on the screen.

I found the CYPD3125 might be partly damaged: the VDDD, VDDIO and VCCD are measured to be short circuit to GND.  But the chip is working as I described above.

The programmer is a miniProg3. Below is the connection of the SWD connector:

Here is the connector pinout:

Pin 1: +5v

Pin 2: GND

Pin 3: reset

Pin 4: GPIO P2.0  ((pin 16 in CYPD3125)

Pin 5: GPIO P2.1  (pin 15 in CYPD3125)

and part of the schematic of the target board:

Could you tell me if the wired connection of the Pin 1 of the SWD connector to VDDIO and VDDD caused the chip partly damaged?

Thanks,

Derong Yuan

[ShifangZ_26]

Hi Derong,

Pin#1 of SWD programming is VTAG, it is about 3.3V or 5V. It should be not damaged. If you suspect the chip was damaged, you could contact your local FAE to support you to do Failure Analysis.

Best Regards,

Lisa