SMD MOSFET help with identification please

Hi everyone,

I've found out that some faulty components I want to replace in my laptop are 3-pin MOSFET devices, N-channel from what I can tell. I can switch them on with my meter so the diode reading from source to drain changes to read short-circuit instead, etc, so I'm quite sure they are MOSFET devices with source, gate & drain connections. Can anyone help me identify what part numbers they have so I can get replacements please?

Number on devices:

7ER9G

But the 'R' has a small horizontal line above it, like this:

-
R

So it's a smaller letter than the others, as the line takes up row space.

Same ones on same board from identical laptop but someone else's has markings with the 7E and the small R with line above, but last 2 digits are different, so I assume they are simply date markings or something, and only first 3 digits actually help identify the component.

I've found a multitude of SMD code pages on the net, but the ones for parts starting with 7E do not match up with the parts I have at all, so I don't know what to do.

Maybe someone here has come up against this problem and knows how to work it out please?

Many thanks,
James

Your best approach is to use the Digikey search to find a part number based on the drain voltage and current needed. You have a working PC board, so measure the drain voltage and gate voltage with an oscilloscope. You will probably have to estimate the current requirement based on it's location in the circuit. The MOSFET is probably logic level drive, but the scope will show that.