Ether, I assume you got the PN FDP8441 from an actual Jag as it is not one of the PNs in their spec sheet?
In any case it is very similar to the best performing one on their list.
Ahm, dating myself here, MOSFETs were not in my undergrad EE curriculum, hence my icon is the much loved 2N3055
Just looking at the datasheet for FDP8441 and the Jag Spec:
1. the FDP8441 max switching times are 77ns ON, 147ns OFF that is about 0.3% of the PWM cycle. So how much power can be relesed in such a short time into an inductive load? Further, the Watage and Temp calcs earlier assumed a 100% PWM duty cycle, anything less will double the FETs over which to dissipate the energy. Worst case would be 99.9% PWM duty cycle. I agree some additional wattage should be added but it may be unecessary?
2. What are all the data about Joules and Coulombs, I would love oto hear a scientific explanation on switching energy, anyone?
3. The Jag datasheet has a writup on how the MOSFET is used to sink motor current thus reducing power dissipation compared to a diode based solution. Maybe Victors don't do that so that would be a -ve for the Vic in this debate.