Is it ok if the mosfet chips don't match?

cns00 · November 5

My Alienware 17 r5 laptop has 6 AON6962 mosfet chips. A few of them have burn marks on them and need to be replaced. Arranging new AON6962 mosfet chips could be tough because they are no longer being made.

I have heard that some people who are unable to arrange new AON6962 mosfet chips are using AON6992 mosfet chips as a replacement chip because its specs nearly match AON6962 mosfet chips.

I want to ask if I replace the burnt AON6962 mosfet chips with AON6992 mosfet chips then is it ok if I keep the remaining AON6962 mosfet chips or I also have to remove them and put AON6992 mosfet chips instead of them so all the mosfet chips are AON6992 mosfet chips?

Mayday793 · November 5

Hey,
Im comparing the specs on these two pages:
https://www.aliexpress.com/i/1005005538795665.html#nav-specification
https://www.aosmd.com/res/datasheets/AON6992.pdf

I'm looking at drain voltage and drain current and theyre the same.
RDS (Resistance for drain-source when on) is nearly the same but this shouldnt matter in most cases since pcb traces probably greatly out power(out value? is a greatly bigger number??) the resistances. i.e. this mosfet is measured in miliohms and the pcbs traces are in the ohm range(maybe 0.1ohm range, though still way bigger so that small change is negligable.)

I would go for it if you've got the ability to swap them. These look like SMD parts with no leads (quad flat no leads A.K.A QFNL). These are VERY difficult to replace yourself, I learned that the hard way in my engineer capstone project.

I have in the past done the sourcing for the parts for the boards i use in my hardware lab (networking equipment). So i have some experience trying to deal with parts being out of stock. With the mosfets you're mostly looking for the activation voltages which seem to match on these two models.

Hardware electronics can be lenient sometimes and i think this is one of those cases

cns00 · November 5

2 hours ago, Mayday793 said:

I would go for it if you've got the ability to swap them

Please answer my question. Do I have to replace only the burnt chips with AON6992 or I have to replace all of them?

Mayday793 · November 5

Sorry i'm sick and obviously didnt read your full post.

You shouldnt have to replace them all.
While its possible you might need to replace them all its highly unlikely that replacing a few would do any additional harm, so its worth a try. There no way to know sure without looking at a schematic to assess the risk of replacing these parts. Though as i've said above the parts are nearly identical so the operation of both chips will be the same.
My next questions would be is why those mosfets burnt out in the first place. You may just run into the same problem with more burnt mosfets once you replace some.
Also how do you plan on replacing them?