So a friend was explaining to me a while back the theory about why he thinks our laptop is behaving the way it is, and from what I’ve researched on the internet – it checks out. The majority of those “fix your dead laptop for cheap” places do the exact same thing: replacing the MOSFETs responsible for power management and then the majority of laptops will come back to life.
So I carefully tore apart our laptop one more time and traced as much of the board as I could, before identifying several of the components on the board. It looks like it has two MOSFETs, Fairchild FDD6685 (which are dirt cheap on Mouser). They’re not too teeny-tiny either, so I’m pretty confident I can replace them myself if I had the tools.
The first thing I lack is a good soldering iron. We used to have one that would have done the job nicely, but I have no idea what happened to it – probably got stolen when Larry’s shop got ransacked by the cut-throats at the flea market after his stroke. The only soldering iron I have now that I use for automotive stuff is just your typical “plug in and go” soldering iron, the tip of which gets far too hot for me to risk using it on a ~$600 laptop.
So I’m shopping eBay for soldering stations, looking for something that meets all the criteria I want (grounded, ESD-safe, temperature controlled) but isn’t too crazy expensive. So far no luck. I think I can by without “ESD-safe” by using a grounding strap on my wrist with a grounded soldering iron, which is probably smart since I’ll hardly be working in a clean room so I’ll want to take all the ESD precautions I can.
So here’s hoping I can get the thing running again, if not I can always core the motherboard and buy a new one for about $250. But a handfull of components and a new soldering iron isn’t going to come out to that much, so this is the preferred route.
All newer soldering equipment is ESD (ElectroStatic Discharge) safe.
Its more a matter of if the testing to claim so was done. Don’t fret about that.
We (the human) are the static generators, A wrist strap is adequate if you have concern.
I never wear one anymore. For an iron get one with adustable temp,
lots of affordable tips in different sizes, and a good quality iron holder.
Heres one I found for you on ebay that qualifies. Item number: 270364639243
$85 plus shipping. I run Hakko that its a clone of, lots of tips that last a long time if not abused.
Larger multileg chips can easily be removed with a $15 Harbor Freight heatgun if careful. You can use aluminum foil or pieces of scrap sheet for heat deflectors if you are worried about desoldering a nearby component. The surface tension of the molten solder will hold parts in place as long as they are not mechanically agitated. You can also use this for resoldering but it is far trickier.
-Ken
Thanks for the reply!
I already sucked it up and sprung for a Hakko 936-12, so hopefully it does the job because they look like nice units. It hasn’t got here yet and I still need to pick up the replacement parts from Mouser. I’m going to replace the two FDD6685 MOSFETs, but I’m unsure of what supporting components around it need to be replaced – I’m still doing research into what all could possibly fail when the fets go. I almost feel a bit silly, but the cost of parts aren’t expensive when compared with the cost of an entire motherboard so I think it’s worth bumbling through it once just to see if I get lucky.
I’ll keep the heatgun in mind, but most of the stuff I’m thinking about replacing is all pretty easy soldering anyway. If I find something else to replace before I make an order from Mouser and it necessitates that I’ll definitely look into picking one up.
Thanks for taking the time to point me in the right direction.