Fixing broken Dell Laptop power supplies

Preamble

Following on from Dell M6700 or M6800, there are a lot of laptops sold without power supplies or chargers. This made me wonder:

  • Is it because they blow often?
  • Why is that?
  • Are they plugged into power hungry docks
  • Are they underrated?

See M6600 Owner’s Review – Warning – Large pics – Personal Opinions for an interesting break down of the power supplies and current draw.

Anyway, I thought that instead of buying an expensive new, or second hand, supply (the 240 W or 330W can go for up to £100+), is it possible to to fix them? Is there a common failure mode? A recurring point of failure?

Continue reading Fixing broken Dell Laptop power supplies

Optimal routing of CD4017 outputs

Preamble

The outputs of a CD4017 Decade counter are not the most strategically placed. In fact they are downright frustratingly placed. Routing between the IC and an inline ten pin header is not the most pleasant of tasks.

First off, should the ten pin header be placed on the left or right hand side of the IC? The left hand side would seem the most logical seeing as most of the outputs are down the left hand side of the IC. In that case, then three tracks are required to route three pins from the right hand side of the IC before routing even begins.

Please note that this is a work in progress, and will be for some time, I believe.

Continue reading Optimal routing of CD4017 outputs