Hi, I endeavor to avoid the high wattages seen by R5 and the current loss through R5 (that is not going through my solenoid). On the other hand, I do not want to increase R5 because then I cannot cycle the solenoid according to the preferred frequency (10-20 Hz). I was thinking I could add a p-channel depletion-mode MOSFET above R5 that would be signaled at the same time as the input to the other 2 MOSFETs and prevent current from running through the cap charging leg. Does this idea have any promise? I can't figure out how to simulate it. Specifically, I can't figure out how to bring the depletion p-most gate to 0v at the same time the 3.3v from the micro is triggering the N-channel MOSFETs. Any help/suggestions would be appreciated.
Note: The LM317 is there because I am trying to limit the average power dissipation in the solenoid to 9W, regardless of the switching frequency.
Ref- https://archive.ednasia.com/www.ednasia.com/ART_8800523816_1000007_AN_dac7d6d3.HTM
(Image of example circuit schematic from the same publication attached)
Note: The LM317 is there because I am trying to limit the average power dissipation in the solenoid to 9W, regardless of the switching frequency.
Ref- https://archive.ednasia.com/www.ednasia.com/ART_8800523816_1000007_AN_dac7d6d3.HTM
(Image of example circuit schematic from the same publication attached)
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