Does anyone know roughly how to estimate the voltage and current capacities of a fly wheel diode being used across an inductive load? Like the size of the voltage spike involved during a worst case switching as well as the fly wheel current (if I use a rough V = L*di/dt calculation, using a conjured up maximum current and switching time to guesstimate di/dt I get rough voltages, but I have no idea how accurate they are and I don't know how the current is calculated either).
Even very rough ratios just to get an idea would be nice. I just have no idea how high the voltage spike could be other than it could be higher than the supply voltage, and for the flywheel currents...I have no idea how big those are at all. For example, a 6V motor with a current draw of 6A might need a flyback diode rated X times the supply voltage and Y times the current draw. Or something like that.
Even something as rough as the flywheel current is less/more than the load current draw would help.
I believe it is only the peak ratings that matter in this case, rather than the continous ratings, right? Since freewheel diodes are dealing with spike-like events.
Even very rough ratios just to get an idea would be nice. I just have no idea how high the voltage spike could be other than it could be higher than the supply voltage, and for the flywheel currents...I have no idea how big those are at all. For example, a 6V motor with a current draw of 6A might need a flyback diode rated X times the supply voltage and Y times the current draw. Or something like that.
Even something as rough as the flywheel current is less/more than the load current draw would help.
I believe it is only the peak ratings that matter in this case, rather than the continous ratings, right? Since freewheel diodes are dealing with spike-like events.
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