STUSB4500 datasheet VCONN pin confusion

[PDobo]

I am designing a device using the STUSB4500 in QFN-24 package. In the datasheet, pin 3 is both specified as NC and VCONN.

The pinout says it is NC, but in any example schematics, this pin is shown as VCONN.

In different resources, this pin is either being treated as NC, or connected to GND.

The STREF-SCS001V1 reference design has pin 3 connected to GND.

Below are some reference documents, together with revision dates and how this pin is treated on schematics:

The STUSB4500 datasheet was revised on 03-Jul-2018 (pages 3, 4 - NC)

The STREF-SCS001V1 was revised on 31-Jul-2018 (page 2 - GND)

The UM2533 was revised on 08-Jan-2019 (page 3 - GND)

The STEVAL-ISC005V1 is not dated, but the schematic is the same as in the datasheet (page 1 - NC)

Which approach is the correct one?

Cheers!

[PDobo]

I asked this in the Service Portal.

Today, the case was closed, and the only insight I got from ST was:

"The application note and user manual which pertain to part STUSB4500 are on the product page under the "Resources" tab."

Now that's something I didn't think about! Thanks ST :(

Has anybody tested both approaches (either connecting Pin 3 [VCONN] to GND or leaving it NC) in a production device, or had hands-on experience with the reference design board?

[Gregory Go.]

Hello,

VCONN is a an additional source of power which is needed for e-marked cables (EMC).

The VCONN power can only be provided by the USB-C Source side.

So it doesn't exist on the STUSB4500 which is a Sink only.

Indeed there is a mistake in several schematics which mention VCONN on pin 3.

So for the right pin function, you need to refer to STUSB4500 datasheet at Table 1 "Pin function list".

It is described that pin 3 is NC (Not Connected). So you can let this pin floating or connected to GND.

Best Regards

[PDobo]

Thank you, Gregory, this is the clarification I wanted.

Have a nice day!