>But, I have noticed there is an option for isolated and non-isolated.

>Can someone tell me what the difference is and which one would be more
>appropriate?  I'm still trying to find more info on the difference between

Without looking at the data sheet for the devices concerned, I suspect the
difference is if the tab of the TO-220 package is isolated from the chip or
not. If not then you will probably need electrical isolation from the
heatsink. If it is isolated, then you MAY get away with not isolating the
package from the heatsink, but I would still expect to see a warning inside
the case that the heatsink could be electrically live.

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