There are two ways that stall currents are usually handled: Most commonly you just over rate the controller enough to deal with peak currents. This works fine unless things are heavily overvolted or you're using particularly large motors. The other alternative is to use current limiting as you say, where you read off the current and ramp down the input until it comes back down below the limit. Charles Guan has many pages on the development of the Rage Bridge which is definitely worth a read; this uses current limiting so you can get an idea of how it works. For featherweight motors though I'd advise just over rating the controllers enough to handle what you need. A good page to read for that is Chuck McManis' MOSFET rating page , which gives you an idea of what FETs you need. For an 18v 775 you'll probably want a continuous rating of about 60A or near enough.
As for components, I'd advise using HIP4028 driver chips to drive the MOSFETs; I tried using other things but this is by far the easiest. Few things to watch out for though with the HIP4082; need to run them on at least 10v (I use ~15v), have a PWM frequency of >1kHz, and don't let the high side signals go above about 98% duty cycle else the charge pump will run out of juice. Probably won't make much sense atm but hopefully after doing some research you'll see what I mean :L
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