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Parting Note on: OEM vs Universal AC Adapters- Dispelling a Myth
This post comes to you as a final, parting note on the subject of OEM vs Universal AC adapters due to my last account being blackballed after a single post. Deletion of the post in question was understandable even though I may not agree with it. But, to render my account unable to access even the most basic search features, make ANY posts, etc. was wrong. Therefore, at the risk of immediate and, subsequent deletion I post this under the second account I had to create just to speak out and, be heard. There:
Tell me again, How a Dell OEM AC adapter is the ONLY adapter that will "charge" a Dell laptop?
The following seems to say otherwise...
Latitude E6400 - turned off but, plugged into AC adapter...(note the illuminated charge LED)
Screenshot of BIOS screen...(90w, charging and, at 95%)
Windows screenshot after boot-up (plugged in, charging, and, NOW at 96%)
I may be the luckiest person in the world in obtaining either a "one-of-a-kind" Dell E6400 laptop or, a "one-of-a-kind" Universal AC adapter.
Maybe I have "BOTH." Either way, according to at least one source on this site (SpeedStep)
"For more than 90 percent of Dell Chargers that is not the case.
For some of the Netbooks like Mini9 Mini 10 it works with just about any charger.
However for The Latitude and Inspiron and Alienware and others that use the charger with
3 wires aka a tiny pin in the center it isn't wrong. Only a Dell Charger will charge the battery even if its new. If the tiny pin is broken or the Power Jack is broken it will not charge the battery. If a new Adapter does not work the motherboard will need to be replaced.
My knowledge is relevant and goes back more than 25 years. If turned on in the bios it will warn you about this by saying "The AC power adapter type cannot be determined. Your system will operate slower and the battery will not charge. Please connect a Dell AC adapter or higher for best system operation""
Still stand by your statement, SpeedStep?
MicroTest
934 Posts
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April 20th, 2013 06:00
I just googled - your Targus adapter is obviously designed to be compatible with a lot of laptops from different manufacturer - including Dell !
You should take a very close look at the specific "Dell" plug.It must be a three wire system.Without the third - control wire - it is NOT possible for the BIOS to tell you what kind of power adapter is connected to the system.
Kompwerks
3 Posts
0
April 20th, 2013 10:00
Yes. The Targus adapter was OBVIOUSLY designed to work. And, of course the adapter "tip" has a center wire. However, as shown in the first pic posted, it has ONLY 2 contacts( - and + ).
I detect neither continuity or, voltage when testing the center element of tip.
MicroTest
934 Posts
0
April 20th, 2013 12:00
You will measure no voltage on the centre pin and not getting any continuity because the Dallas chip is powered over its control wire when connected to the laptop.The Dallas "invented "One-wire" chip derives its supply voltage from the incoming control signals.
As I have a different power adapter I cannot tell you where exactly the third contact must be - please check out the picture below.
Kompwerks
3 Posts
0
April 20th, 2013 15:00
If what you are saying is correct then Targus has not only incorporated the use of the Dallas chips, and it's proprietary "1-wire" architecture but, managed to do so in a way that eliminates the use of that "third" wire connection, altogether? The only way possible that comes to mind would be by embedding the DSxxxx chip into the molded plastic adapter tip, itself. However, without going into extreme detail, I understand the necessary method/means of their use precludes this from being possible. It (Dallas chip) needs to be located either in laptop or, adapter for technical reasons.
I still believe the pictures speak for themselves, but...
Here is the point of connection between the Targus adapter cable and the tip for use with Dell laptops. As you can clearly see, there are no 'hidden' wires making any connection here. Therefore, it is logical to assume that if there is NO CONNECTION, there would be NO "1-wire" connection leading down the cable to adapter, either.
The tip, of course, has the prescribed "center wire" as you can see.
However, to the best of my knowledge, this "1-wire" connection goes no further than this adapter tip.
MicroTest
934 Posts
0
April 20th, 2013 15:00
That is an excellent idea and absolutely possible ! The Dallas chip plus a simple pull-up resistor is tiny enough to fit into the tip.As I already mentioned the Dallas chip is not powered by the power adapter itself and only shares the grounding (-) with it.
I guess that solves the mystery about your Targus adapter.
Should your adapter ever fail - total loss of power - you could then still use the Targus tip in connection with any available non-Dell power adapter,just make sure that the wattage is more or less the same and the polarity is fine.