Consider that two identical MOSFET $($ and $)$ in the separate cases, mounted on a

common heat sink. The devices are in TO$-220$ packages and have a thermal resistance

from junction to case of $*+,=1\mathrm{.}2"/.$ The interface between the case and sink has a

thermal resistance of $*,-=0\mathrm{.}2"/,$ and the thermal resistance between the sink and

ambient is $*-/=0\mathrm{.}8"/.(20$ pts$)$

$+$

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$2$

$($a$)$ Draw the equivalent thermal model for the thermal system.

$($b$)$ If the devices are dissipating the same power I$0"!!,(=0"!!,)$ K and $/=40",$ what

is the maximum power that can be dissipated in one MOSFET when $2(,345=$