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Improved coupled L version.
"The coupled inductor not only provides a smaller footprint but also, to get the same ripple current, requires only half the inductance required by a SEPIC with two separate inductors."
On the left, I added a generic PWM gate driver. The pulse width conveniently equals the wiper position. The circuit of interest is thrown together directly from the first figure from, "Designing DC/DC converters based on SEPIC topology" by Jeff Falin
See: www.ti.com/aaj
Q1 is loosely based on the irfz46n. Rds(ON)=16.5mohm, Ids(MAX)=53A
I just cobbled this together to 'follow along' with the design doc and was surprised to find it operating passably first try with the parameters I guessed. That said, I feel this layout (my only real contribution here) might make a good starting point for others like me wishing to study the sepic. I post only as a show of interest, not a show of understanding. Take it or leave it.
And as always, comments welcome. :)
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