TUSB321: Charger with data passthrough

Blaž Kvas

Part Number: TUSB321

Hi,

We are currently working on a car USB C charger that will also have a data passthrough.

So, the charger will have a USB C port that will connect to a device that needs to be powered. This device will also transmit data so it's acting as a power sink but a data source.

Currently power is not managed and the device is connected directly to the Vbus (not USB C standard).

Charger will also have a USB A port that will also be powered. Data lines from USB A to USB C are connected together to allow a USB flash drive to be connected to USB C device while also powering them both.

We used TUSB321 for this since we already use it on other products and tried to set the charger as host to avoid any problems with users that will try to connect a UFP to DFP device that also delivers power.

We are trying to avoid any expensive PD ICs so if you have any other solutions that will be great.

Best,

Blaz

over 3 years ago

0 Brian Zhou over 3 years ago

TI__Guru*** 147055 points

how much power for charger? does it >15W?

Regards

Brian

0 Blaž Kvas over 3 years ago in reply to Brian Zhou

Prodigy 60 points

Hi seems that my last reply didn't go through.

Yes the USB C output must provide 3A and the USB A output must provide 1A.

0 Brian Zhou over 3 years ago in reply to Blaž Kvas

TI__Guru*** 147055 points

for CC controller, max power is 3a x5v=15W., so may not enough for your application

Regards

Brian

0 Blaž Kvas over 3 years ago in reply to Brian Zhou

Prodigy 60 points

Ok, but this is not related to the host device functioning.

Currently we have a charger already made and are having trouble with the host/device modes.

The charger is fixed as host and when you plug in a device the ID pin is pulled low indicating that a device is connected.

The problem arises when the charger is then powered off. The device (phone in this case) immediately switches to host mode and supplies the VBUS. After the input power is delivered to the charger again the modes don't switch back. The phone stays as a host which is a problem since the charger then doesn't supply the power (ID pin is connected to the VBUS switch).

0 Brian Zhou over 3 years ago in reply to Blaž Kvas

TI__Guru*** 147055 points

yea, for CC controller, once it is configured as DFP or UFP, it will not change role until get reset or re-connect the CC cable.

PD controller can change power role .

Thanks

Brian

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TUSB321: Charger with data passthrough