TPS25751EVM: evaluate charging tablet with USB-PD and fixed 9V supply using EVM

Hi,

Thanks for reaching out on E2E!

As part of the PD spec, you will be required to also support a 5V 3A PDO, but otherwise you should be able to do a 9V @ 3A PDO with the EVM if paired with a BQ EVM as well. The GUI already has our supported BQ devices listed and will automatically configure the charge out feature. All you would need to do is adjust your PDOs.

Thank you,

Kevin

I am trying to evaluate the TPS25751 using the TPS25751-EVM to charge a tablet with a fixed 9V@3A supply connected to the PPHV.

Is this possible without a BQ 

Also when I select config as TPS25751 Source and Sink without the BQ (2 PDO +5/+9) the TPS25751-EVM does not connect to the tablet as a charging source

The choice for power source only allows for 5V source

Suggestions

The Table is a Samsung Galaxy Tab S7 or 8S

Here is the latest I have somewhat working but best case Charge on a Galaxy Tab S7 is 5V@1A.

JSON file attached?

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"device": "TPS25751",
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"vendorId": "0000",
"productId": "0000",
"version": "1.0.0.2"
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"configuration": {
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Hi,

Thank you I got the JSON!

Give me until Friday to get to this and take a look.

Thank you,

Kevin

Hi,

any luck with the JSON?

Thanks,

Rick

Hi,

Sorry for the delay here I will take a look tomorrow.

Thank you,

Kevin

Hi,

Did you get a chance to review the JSON?

Any comments?

Rick

Hi Kevin,

I have done some additional testing.

I purchased a HUSB238 board, when attached to the 25751-EVM the EVM produces +9VDC out.

Testing with a Power-Z from ChargerLabs the EVM on its own does not indicate and Fast Charging Capability.

When connected to the Samsung Tab S7 the Power-Z indicates PD3.0 27W although it is charging at 3.7W.

Any thoughts?

Rick

Hi Rick,

Sorry for the delay here as I was OOO travleing.

I am glad as it seems that you are getting a 9V output!

What is the battery percentage of the Samsung tab? If we see 3.7W charging the sink could be limiting its charge current.

Have you made additional changes to the JSON? It would be better for me to take a look at that if you have made modifications!

Thank you,

Kevin

Hi Kevin,

So I am getting 9vdc on the test board but not the Samsung S7.

The Json is the same.

I also tried as a source only 5v @ 3 A but only charges at 5V@.6A or 3W when tablet is at 27% charge.

I went through the settings again and could not see what could explain the interaction.

Thoughts?

Rick