Are Dell's PS_ID and HP's ADP_ID interchangeable across all models?

[boyop]

Hi All,

So I'm trying to get into laptop motherboard repair and am having trouble understanding Dell's PSID issue.

According to a site I come across :
https://hackaday.com/2014/03/03/hack...dentification/
Original Dell adapters use a ds2501 to communicate with the laptop SIO using the '1-Wire' system to inform the SIO of the chargers current rating.

The confusion I have is, do the adapters communicate anything other than that? If not, is a single charger sufficient to use across all models that the charger fits (providing the current rating is the same)?

Also, The same seems to be the case for HP's ADP_ID. So I would like to apply all of the above to the HP chargers too. If they even use the same 1-wire system?

[piernov]

Re: Are Dell's PS_ID and HP's ADP_ID interchangeable across all models?

HP use a resistor between 19V and center pin, completely different from Dell and not compatible. Any HP power brick with correct tip and same or higher power rating than what the board requires will work. With lower power rating the machine won't turn on if battery is missing/dead/discharged.

For Dell, any Dell power brick with correct tip and same or higher power rating than what the board requires should work. With lower power rating, the machine can often still turn on, but it shows a warning during POST or in the Setup, may throttle and may not charge the battery.

[boyop]

Re: Are Dell's PS_ID and HP's ADP_ID interchangeable across all models?

Thank you Piernov for your excellent reply. That has cleared up a lot.

This leads me to an issue that I'm having regarding the ADP_ID pin on the EC.

That centre pin on my adapter is 18.7v and I'm getting only 0.5v approx. on that EC pin. Looking at the schematic, since the Zener diode is there and has a breakdown voltage of 3.6v, I'm assuming that the pin should be held around that 3.6v. Is this correct?

Also, As a little exercise, I removed all of the components in that circuit, leaving only the voltage divider and it is still only 0.5v. I also cut the track to the EC. (see attachment)

I have come to find that the DC connector is causing the voltage to drop down to 1v before the voltage divider. I'm trying to understand why that is? Is the DC connector designed to do that? I have tried to connectors and it's happening in both cases.

Many thanks in advance!

[ktmmotocross]

Re: Are Dell's PS_ID and HP's ADP_ID interchangeable across all models?

resistance on that adp line?

middle pins is vulnerable to damaged connector which put 19V to middle pin. burning EC

[boyop]

Re: Are Dell's PS_ID and HP's ADP_ID interchangeable across all models?

resistance on that adp line?

middle pins is vulnerable to damaged connector which put 19V to middle pin. burning EC

Hi, Resistance on the ADP line is 10K ohms.

Mind, I have now cut the track to the EC. However, it was 10K even when the track was in tact. The EC didn't heat up and the laptop is/was not drawing excessive current (20mA before pressing the power button and 150mA a few seconds after pressing the power button.

The middle pin on the adapter is 18.7v. I assumed that this is ok since the adapter is working fine on my other hp laptop and is supposed to be compatible across all laptops.

What's more, if I bypass the dc connector and connect the power supply directly to the board, the voltage doesn't drop to 1v on the adp line before the voltage divider as shown in the screenshot above.

With the power supply going through the dc connector, it drops to 1v on that adp line. I'm wondering, is there a resistor in the dc connector at all?

[piernov]

Re: Are Dell's PS_ID and HP's ADP_ID interchangeable across all models?

No laptop model number, no motherboard model number, no description of the issue, the symptoms, the history, the troubleshooting steps already taken…Also original post was mainly talking about Dell and now it's an HP laptop, doesn't make a lot of sense.
https://www.badcaps.net/forum/showthread.php?t=88758

[boyop]

Re: Are Dell's PS_ID and HP's ADP_ID interchangeable across all models?

No laptop model number, no motherboard model number, no description of the issue, the symptoms, the history, the troubleshooting steps already taken…Also original post was mainly talking about Dell and now it's an HP laptop, doesn't make a lot of sense.
https://www.badcaps.net/forum/showthread.php?t=88758

I apologise about not providing details of the laptop, I initially intended to ask a general question that spans across all models rather than a specific model and the discussion digressed.

Nonetheless, I will start a new thread with details of my case.

Thank you