Laptop Power Supply

Thread Starter

darknys

Joined Apr 24, 2008
8
So, I've got a massive laptop, and it requires a ton of juice. The power supply is rated at 7.89A @ 19V. I'm on my third power supply in as many years, because I travel with this thing everywhere, and the only AC adapter has a serious design problem.

The AC cable has a socket, and can disconnect, but the DC side is just a cable running directly in to the box. After a few weeks of being coiled and placed in the laptop bag, the torque on the cable builds up to the point where the strain relief cracks. It's a coaxial power cable, and after the strain relief goes, it's only a matter of time until the outer conductor is broken.

Right now, it's sitting on my desk, functioning, and only very occasionally emitting snapping noises and ominous smells. (No, I will not leave it plugged in unattended.) I have purchased another, but I would like to repair, and perhaps improve, this one.

So, my questions are these:
The current construction seems like the outer conductor is just gathered in to a bit of shrink tube and soldered in place. The inner conductor is just soldered directly. I think I can cut the DC power cable and replicate this on my own, and it should work. Is this a correct assumption?

As an improvement, I would like to place a socket in DC side so that this does not happen again. However, I've gone through the Mouser.com catalog, and I can't seem to find a power socket that is rated for the rather large requirements of this system. (19V, 7.89A) Obviously, such sockets must exist, because there is one on the end of the cable that plugs in to the laptop. Can someone point me in the correct direction, or is there something I'm missing about the power rating?

Thank you very much for any assistance.
 

kubeek

Joined Sep 20, 2005
5,795
I changed the cable once, the only problem was that the adpter is not made to be opened, so you have to use some tape to hold it closed after you change it.

As for the connector, the only factor is the physical size of it. You could use some of the standard small dc jacks, which probably should stand the charging current, but it isnt for sure. On the other side, you can go for something bigger, like an XLR connector which has a lock to be securely attached and you can be sure it will hold the current.
 
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