> How many FETs are you planning to use?  Bear in mind that whilst
> the full load current of the motor is only ~21Amps, the stall current
> will be much, much higher

Some time ago I helped a friend out repairing golf carts (trolleys,
not cars) of various makes. All had at least 3 FETs, the better ones
had 4 or 6. Although none of them used a micro and had less-than-
optimum power bands. If it were me I might use a look-up table to
set the PWM. For example, maybe the first 10% of the pot makes
very little difference in terms of getting the motor going against the
load, so linearly converting pot position to PWM duty is not the
best way. And monitoring motor demand, even simply comparing
factors such as current drawn versus revs versus PWM (eg going
up or down inclines), can help minimise the need for constant manual
speed controlling


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