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Old 03-30-2015, 04:29 AM
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Matthew Jones Matthew Jones is offline
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Originally Posted by wayne.ct View Post
Matt, could you explain a bit more about the dynamic in this circuit and elaborate a bit on your explanation? Thanks for helping.
So if you have a power source, then a switch, then a load, then ground, and you turn the switch on get power flowing, then cut the switch off You will get a small surge of voltage via an Arc. Any time power jumps across air its a transformation of power from current to voltage. It steps up. It also has the physical property of something in motion wants to stay in motion like fly wheel. This is actually a pretty well known effect.

So the same thing happens in a diode. The diode is in front of the load, you turn the current off with the transistor. The diode has capacitance between the anode and cathode so it stores current. When the diode substrate is turning off that bit of current left then basically arcs into the load causing a boost of voltage.

You can maximize this effect by following the data sheet and the "Turn Off" time of a given diode and pulsing the diode at 30% duty cycle.

Remember though this is not free energy in fact its probably a loss of about 30-40% of total power. But the closer you end up to the turn off time and capacitance the more efficient you get.

Hope that helps

Last edited by Matthew Jones; 03-30-2015 at 04:31 AM.
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