TPS65987D: Port 0 Source/Sink GPIO event unexpected behavior

Ilya Tsunaev

Part Number: TPS65987D
Other Parts Discussed in Thread: TPS65987, BQ25713,

Hi,

We are seeing strange behavior when configuring the TPS65987 profile to assert GPIO20 using "Port 0 Source Sink Event" when it is Sink. This is the way we have it set up.

There are 2 issues,

1) instead of asserting and stay high, we are seeing a toggle instead, the lines goes high for several milliseconds and then goes back low.

2) When we use same even, simultaneously, with another GPIO (GPIO1 in our case), the GPIO20 does not even change states.

Is this expected behaviour? If not could you please help understand the issue?

Thanks,

Ilya

over 5 years ago

0 Kedar_Sirdeshpande over 5 years ago

TI__Expert 3370 points

Hi Ilya,

Just for my understanding, are you seeing a stable PD connection on the Type-C port?

Regards,
Kedar

0 Ilya Tsunaev over 5 years ago in reply to Kedar_Sirdeshpande

Intellectual 305 points

Hi,

Yes, the connection is stable. The contract is negotiated and connection stays at negotiated voltage.

Thanks,

Ilya

0 Ilya Tsunaev over 5 years ago in reply to Ilya Tsunaev

Intellectual 305 points

I made a mistake in initial post about the polarity.

When I set "GPIO Polarity = Inverted Event" I actually see that the GPIO goes low briefly (6-7ms) and then goes back high:

When I set "GPIO Polarity = Direct Event" I see that the GPIO goes high briefly (6-7ms) and then goes back low(shown along side vbus):

So to restate the initial problems I actually see 3 of them.

1) instead of asserting and stay high, we are seeing a toggle instead, the lines goes high for several milliseconds and then goes back low.

2) When we use same even, simultaneously, with another GPIO (GPIO1 in our case), the GPIO20 does not even change states.

3) The polarity of the event doesn't seem to match the GPIO state.

I can share the App Config project if there's a way to upload it "privately".

Thanks,

Ilya

0 Georg Mussenden over 5 years ago in reply to Kedar_Sirdeshpande

Intellectual 280 points

Hi Kedar!

Quick question, what does TI recommends to drive the BQ25713 OtG pin, which we have wired to GPIO1? I believe it ought to be as follows:

The GPIO20 is of opposite polarity as it drives something that needs to be a High when the TPS65987D is sinking and a Low otherwise:

Both must work simultaneously!

Thanks,

Georg A. Mussenden

0 Kedar_Sirdeshpande over 5 years ago in reply to Georg Mussenden

TI__Expert 3370 points

Hi Georg,

Could you please create a separate E2E for this question? The correct expert will pick up your thread and work with you on your query.

Regards,
Kedar

0 Kedar_Sirdeshpande over 5 years ago in reply to Ilya Tsunaev

TI__Expert 3370 points

Hi Ilya,

I have sent you my details in a private message.

Regards,
Kedar

0 Ilya Tsunaev over 5 years ago in reply to Kedar_Sirdeshpande

Intellectual 305 points

Hi,

Are there any updates on this issue?

Thanks,

Ilya

0 Kedar_Sirdeshpande over 5 years ago in reply to Ilya Tsunaev

TI__Expert 3370 points

Hi Ilya,

Sorry about the delay. I took a look at your project settings. The configuration looks to be fine.

Can you try with a default template project and see if you see the same behavior?

Do you have our EVM that you can test on, isolated from your platform? That way we can check for platform dependencies as well.

Regards,
Kedar

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TPS65987D: Port 0 Source/Sink GPIO event unexpected behavior