Hi, hoping this will be an easy one.
I've ordered some MOSFETs, IRL60S216, looking at their data sheet I see package current is 195A.
Now that I'm holding the component in my hand I just don't believe it will do 195A for any length of time. Even the legs don't look like they'd carry 195A, what am I missing?
What is the trick to figuring out a realistic current limit based on a data sheet?
Thanks in advance as always,
Josh
Datasheet: https://www.infineon.com/dgdl/irl60s216.pdf?fileId=5546d462533600a40153565fdf5b2570
Drain current (Silicon Limited): 298A (*1)
- Calculated continuous current based on maximum allowable junction temperature. Bond wire current limit is 195A. Note that current limitations arising from heating of the device leads may occur with some lead mounting arrangements. (Refer to AN-1140)
Sounds like you are right and you are supposed to read the application note to find out how much current you can shove through before the leads blow up. 
Depending on the package and mounting: 160 to 240A.
Rule of thumb without special care in heat management: 75A
IR datasheets lie like this all the time. Stick to 30A per package for a sane life, if you need more than that you'll need something more robust than a PCB anyway, and MOSFETs with terminal blocks built-in are appropriate,
packages like the ISOTOP.
Current specs are pretty irrelevant anyhow, you choose a MOSFET by on-resistance and power-dissipation
in practice. 195A through the IRL60S216 would mean 60W dissipation in a surface mount device....
Is the d2pak what you're basing the 30A off? I bought some of them a long time ago hoping to put a bank of four of them together, to spot weld from an auto battery. ~500ms blips of ~200A.
I don't remember if I ordered a heatsink with them. I don't even remember what they look like for that matter, but I have a milling machine and some aluminium blanks to make one if they do have a mating surface.