On 15/04/2011 00:05, Sean Breheny wrote:
> it is true that MOSFETs have a positive
> temperature coefficient of the "on resistance" when in the OHMIC
> region (close to being fully ON), but in the LINEAR region (where Vdg
> is less than the threshold voltage), the temperature coefficient of
> CURRENT is positive. SO, MOSFETs can be paralleled as long as the
> LINEAR region power dissipation is kept to a minimum, but if you have
> multiple MOSFETs in a partially-on state, they cannot be paralleled
> without ballast resistors (just like a BJT).

References?

I have seen many RF linear amp designs using parallel FETs, none with=20
BJT type "ballast" resistors.
Your explanation doesn't make sense to me either.

--=20
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