Utility that returns psu laptop input voltage?

auriuman78m

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Oct 2, 2008
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Hello, my concern is that of incoming voltage. Primarily on a laptop system but i suppose aside from apc it would be cool for desktops too, but mostly laptops. I use an APC and its utility actually returns line voltage as a parameter. I also know of utilities that will return battery status and voltage. So as a tech it would be nice to know if there are problems with the laptop ac converter. I know, why not just switch out the power adapter to check, right? What if I don't have a spare to swap out? What if I'm just curious? I'd like to know load input voltage. I could just VOM the adapter tip but it just isn't representative of voltage under load. Anyone out there know of anything like this?
 
The problem is most laptops do not provide a "sample point" for the DC input (ie at the DC input jack). Requires an A->D converter which would return a Hexdecimal value for the analog voltage. The software would convert this Hexdecimal value to a voltage reading either thru a look up table, or an algorithm.
 

auriuman78m

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Oct 2, 2008
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I was afraid of that problem. I will probably have to build some sort of custom rig to do this... which honestly may be more $ and time than would be buying a universal with many tips for testing haha. Thanks though @RetiredChief.
 
Also not sure the info (Input voltage) would be without also knowing the current.
A typical AC adaptor (for Li-ion) is rated 19 @ 4 Amps. The output will vary some due to current and if you read say 17 v is that becaues the adaptor is not putting out, or is the current drain loading the Adaptor. Not sure Putting xxx is politically correct any more.

Enjoy