I am using a D36V50F5 at 12V input to supply 5V power. The voltage regulator is wired in parallel with eight ESCs which can cause a significant (>4V) voltage drop on the 12V power system for very short periods of time as the motors begin turning or reverse direction. This quick voltage drop appears to be causing a voltage drop on the 5V side of the regulator that is causing problems with components that need a continuous 5V power supply.
Capacitors seem like the best way to mitigate this problem, but I would love to know if there are any other methods I could try. If I were to try adding some capacitors, should I add them before or after the voltage regulator?
Probably the most ideal solution would be to address the cause of the problem directly by using a more appropriate power supply that could handle the current demands of your motors starting up or changing direction. You could also consider splitting the load between two separate power supplies (e.g. powering four ESCs from each power supply). Alternatively, if your application allows, you could try limiting the acceleration of the motors; ramping the speed up generally helps avoid a large spike in current from overcoming the inertia.
If you want to try adding capacitors, adding them to the 12V rail would probably be best.
