Seemingly odd configuration on a Gateway MX8530 laptop

dostrander

First off, let me state I'm not a laptop person, I'm 100% desktop so my typical laptop configuration knowledge is pretty limited.

A friend gave me this laptop to see if I could resurrect it for him (it's not receiving any power).  It's current configuration (and I've been told that it has worked in this config when he got it second hand) is, 1) Transformer is Gateway manufacture 19V at 4.74A (I have tested the transformer and read 19V at the plug).  2) Sticker on the bottom of laptop states "Input 19V at 4.74A or 6.32A"  3) Battery is Gateway manufacture (original or replacement, unknown) model SGU-413, rating 14.4V at 4800mAh.

Should this laptop have been able to operate with such a wide voltage gap?  Also, with the battery out and the charger plugged in should you be able to read voltage at the battery contact points?  All contacts read 0V.  Please let me know if more info is required.

Thanks

billsey

I'm guessing here, because I've never been involved with these types of design decisions on a laptop... I'd think in that scenario if the battery was not detected it wouldn't provide any voltage to the battery. Since the battery charge function is only activated when the battery needs charging I'd expect it to decide no charging is needed if the battery weren't there...

billsey

Yes, that is a pretty typical design, 19V power input for a 14.4V battery. The higher voltage helps with faster charging, and charging current is backed off as the battery reaches full charge. You should read 14.4V on the battery connector if it's functional. My guess is it has dropped below the threshold voltage needed to continue use. That's a pretty old system, so it wouldn't be unusual at all for the battery to have gone south. As to whether it runs sans battery on just the charger, it depends on how they designed the MB. If the charge current is passed directly to the battery and then the battery provides power for the MB, it's not going to work. If the charge current is sent to a charge circuit o the MB, which charges the battery and provides power for the onboard circuits, then it should work.

dostrander

Thanks for your response.

With the scenarios you stated, "..If the charge current is passed directly to the battery and then the battery provides power for the MB, it's not going to work. If the charge current is sent to a charge circuit o the MB, which charges the battery.."

In both scenarios, with the battery removed and charger plugged in should there be voltage at the laptops battery connections? Or is there circuitry to shut-off power shunted to the battery if the battery is not sensed?

billsey

I'm guessing here, because I've never been involved with these types of design decisions on a laptop... I'd think in that scenario if the battery was not detected it wouldn't provide any voltage to the battery. Since the battery charge function is only activated when the battery needs charging I'd expect it to decide no charging is needed if the battery weren't there...