Ok, After the initial *discharge spike* of the L1, we see a gradual linear discharging vof C11 thru L1
With MOSFET removed, that can happen only if voltage on C11 is greater than voltage on C3 NOTE: The replies below use the component designations from Akula's chematic diagram v2.1: If the MOSFET is in place and switching rapidly, then the junction of L1 & D5 will have a high voltage in reference to ground after the MOSFET opens (in order to keep L1 current continuous). When this voltage becomes higher than the voltage across C3, then D5 will conduct current and charge up C3 (potentially to to a very high voltage which is clamped down only by the LED bank and D6+L2+R3). From 20 > 16vdc (possible feeding the L2 and/or LED array?)
D6 will conduct and allow current through L2 only if the voltage across C3 + the EMF generated by L2 is greater than the voltage on C11. Any current flowing through D6 will charge up C11. BTW: Current flowing through the scrubber composed of R2 and C4 is minimal or momentary. The above is the MAJOR POWER LOOP of the entire circuit. ..... then about 20us into the affair we see a very fast discharge, abruptly pulling the signal towards Zero potential which just as fast reaches an equilibrium @ what appears to be Vcc potential (from the scope shot appears about 12 - 13vdc).
Can you rephrase that? 20μs after the gate edge or sth else ? Question: What is happening simultaneously @ LED array at this moment?
The LED array always attempts to discharge C3 above its combined voltage drop (e.g. 15V). In effect the LED array attempts to clamp C3 to a voltage <= 15V. A resistive load would discharge C3 from the beginning (from 0V), and the circuit would behave very differently with such load. Question: What are the inductances of L1 & L2?
Mutual coupling coefficient is also unknown between L1 and L2. Question: What about the copper tape to ground shown in the Akula diagram, Is it being used here?
I do not know but it is alleged that the copper tape is essential for the OU effect. In a different, albeit related, 3V perpetual flashlight, the copper tape is allegedly placed like this around the inner winding (secondary):
« Last Edit: 2014-04-17, 23:17:17 by verpies »
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