After reading those
clarify coniditons :
fet calculation :
1)Vgs min :
from zero thermal coeffcient , from gaph : Ids , Vgs , to prevent thermal runaway
2)Vgs max : from datasheet Vgss
3)Vds max : From Safe operating Area graph , before thermal instability line, and keep in mind power limit .
project calculation :
1) first model my load , to know its impedance , resistance 2) calculate Vds = Vbattery - Load Voltage drop , Vd = Vb , Vs = Vd-Vds
( stated in pdf that Vds depends on voltage drop of load )
3) controlling Vg so it can be variable or constant , connect it to ground so it becomes zero
4) calculate Id ,from Id , Vds graph at known Vgs
Does these steps are correct , fully understood or i miss something ?
i want to know in Ids ( Vds graph )
is linear region , when Vds before V pinch ? and this region correspond to Rds on limit in SOA graph ?
also does saturation region corresponds to package limited ?
if these are correct what does max power limit corresponds to in Ids Vds graph ?