2N7002 Continuous drain current?
2N7002 is not a very suitable part for this application. Assuming you even have 10V to drive it, the power dissipation (worst case) of 360mW is a bit much for an SOT-23 even if you use 2-oz copper 1 inch square etc. 

Something like an AO3418 would be a lot better- even with 2.5V drive it will dissipate well under 10mW conducting 200mA, and it's not that expensive. The only downside is that it has more gate charge (not usually a problem for PWM at reasonable frequencies), and that it is only rated for 30V rather than the 60V of the geriatric 2N7002.