Troubles with HP pro x2 612 g2

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

yes, i did that. I just tried something else. I did my hot plug, you know, this time first plug the usb c port, THEN the battery. In that case, the readings on the dc mosfets are the usual 11.8V on S and D BUT only 16V on gate ??

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

and sorry for the misunderstanding, I missed a message because of the new page of the thread

[mon2]

Re: Troubles with HP pro x2 612 g2

Ok. This is getting closer...see my last post. The charger IC is performing the selection of the mosfets.

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

so yeah, the first reading were with battery first plugged in then DC charger, and now, the new one are with the reverse

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

do you think I should try to swap it with the other one I have on an old board ? both are named BQ24780S only the other markings below are different

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

I just saw your updated message
So if both jack and battery plugged in but battery first, it shuts down the pc, the batt gate -Error, meant batt Source and Drain- is still 8.3v, The ACOK et ACDET are at 0V
If Jack (i mean usb c) first then battery, the light is on, and then the ACOK and ACDET are at 3.3V

[mon2]

Re: Troubles with HP pro x2 612 g2

So if both jack and battery plugged in but battery first, it shuts down the pc, the batt gate is still 8.3v, The ACOK et ACDET are at 0V

For this case, what is the voltage on the 2 x DCin mosfet pins ?

Do you still see ~12v present on the first mosfet ? Post each voltage reading.

With batt gate @ 8v3, the N-channel mosfet is being told to remain OFF.

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

no, in the case of plugging the battery first, as soon as i add the usb c, it turn the light off. But I still can read the battery mosfet, 8.3V Drain and Source, 14.3V at Gate
The two DCin mosfets are then at 0V S, 8.3V D and 0V G

EDIT sorry, in my previous message I meant 8.3V Source and Drain, not gate

[mon2]

Re: Troubles with HP pro x2 612 g2

Take your external power adapter and flip it 180 degrees and insert back into your laptop under the same conditions.

Anything different in the operation ?

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

no

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

once the pc start on battery, the usb c dc in stop being recognized, per say. No light if I connect anything

[mon2]

Re: Troubles with HP pro x2 612 g2

Do you have any other USB Type C power adapter for testing ? Or another USB type C device that can be used for testing ?

It is possible that the external adapter is flaky and not able to power up the logic board. The power delivery contract is enabled over negotiations. A USB Type C bus analyzer is a good tool to use here to validate on what the adapter and logic board are chatting about, if anything.

Or, the logic board's power delivery controller IC is acting flaky due to some fault of the CCx lines (CC1 is on one side / CC2 on the other side of the Type C connector blade).

Try:

1) Power down -> leave in the battery -> meter in DC volts scale (20V scale is ok).

2) attach the power adapter -> check the voltage of each pin you can see on the logic board - these are small through hole solder blobs for this connector. Red probe on a hole; black to ground. One of your posted pics has clear access to these points.

Measure each voltage. By default, you must see 5v on one combination of these test points. After negotiations, you should see the expected ~12v.

Check each connector pin and post your results with the voltages.

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

I do it. I have one other usb c charger. It s the nintendo switch one. USB C, can negociate from 5 to 15V at 2.6A when the HP goes up to 3A

[mon2]

Re: Troubles with HP pro x2 612 g2

That is ok - try with the Nintendo unit to test the results.

Use the other USB C charger and connect to this HP.

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

ok, meanwhile, I found two 5v pins with hp charger. nothing else

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

Wait, on the nintendo switch adapter, it s only written 5v and 15V. Will it fry something then ?

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

I have a power supply, that can be set from 0 to 30V 5A. I can maybe wire it to the board ?

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

ok, so let's forget the nintendo charger idea.
So, I measured the usb c pins. If I measure themafter the board is on, without battery, only on the usb c charger, It's at 11.83V on two pins.
If I measures them when the board is on battery, and i plug only after a seconde or two the usb c, they stay at 5V.

I suppose that it means the board negociate with the adapter as it should. But then, why isn't the port ok anymore when the battery is plugged in ?

[mon2]

Re: Troubles with HP pro x2 612 g2

yes, agree with your last posting.

Confirm that the external adapter is able to power the logic board everytime without the battery.

On this board, connected to the CC1 & CC2 pins of the Type C connector will be a power delivery controller IC. This controller IC will feature a USB Vbus mosfet. Very likely this mosfet should be visible on the board - that is, the mosfet on the past generation of designs are still external to the controller IC.

Review the board for other controller chips that should look similar to the 24780S - perhaps from Cypress or ST or Infineon (now the owners of Cypress).

Take pics and post them here.

[johnjohnjohnjohn]

Re: Troubles with HP pro x2 612 g2

could it be this one ?