chiques
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even in an ideal world, my circuit Q will only be as high as 9.1
My goal is to maximize the current going through L and C. If I look at the equation for this it seems 'R' is the limiting factor.If your goal is to get a return loss better than -12.8dB, you don't have to use a series resonant circuit.
You need an LC matching network, perhaps just a Γ network will do the job. For this you need to know the input impedance of your circuit.
Not necessarily totally different. Matching your source impedance (e.g. 50 ohm) to LC circuit real impedance in resonance fulfills both, maximum power transfer (s11 = 0) and maximal inductor current.So, you have two goals, first to get return loss better than -12.8dB and second to maximize the current through the series LC circuit.
These goals are not the same, actually they are totally different.
If your goal is to get a return loss better than -12.8dB, you don't have to use a series resonant circuit.
You need an LC matching network, perhaps just a Γ network will do the job. For this you need to know the input impedance of your circuit.
Voltage across the inductor and the capacitor are close, the voltage across the resistor is much lower.L:C ratio is a key factor regarding Q and impedance.
Large L, large impedance, large Q.
Small C, small impedance, small Q.
Since your source is a Sinewave, see if calculations steer you to achieve identical voltage swings on all three, R C L.
Or you may have additional considerations in mind. Example, do you want maximum power transfer?
I'm confused. I'm trying to achieve maximum power transfer. When I connect this circuit to my PA, I'm seeing ~20% of the waveform reflected.So, you have two goals, first to get return loss better than -12.8dB and second to maximize the current through the series LC circuit.
These goals are not the same, actually they are totally different..
My apologies, I read this as being a rhetorical question. The application is to heat up the inductor and characterize the resonant frequency drift caused by the heat rise.Unfortunately you didn't yet clarify what your application is.
This answers one of my questions, the resistor in series is not part of the load. That is correct, the beginning of the load measurement begins at the entry of the inductor.The reflection factor calculation above is nonsense. You say, 50 ohm resistor is modeling source impedance. Respectively it's not part of the load impedance. The reference plane for s11 measurement is between 50 ohm resistor and LCR load.
If I understand vfone correctly, I need an additional LC matching network in between my source and load. Also, in the impedance equation, would the correct 'R' would be the (loss of the inductor + ESR of the capacitor)…?Adding a series resistor generates additional losses and and reduces power transfer to the load. Instead you want a lossless LC matching circuit for maximum power transfer, as already suggested in post #2 by vfone.
Although not clearly stated initially, the OP wants maximum power transfer to the LC resonator ESR. Due to small dimensions and low frequency, there's no relevant radiated or magnetically coupled power involved, all losses can be expected inside the components.
Trying to run this simulation but I don't get what you get.Series-parallel resonator
View attachment 182642
--- Updated ---
Or even simpler, pure parallel resonance. My assumption in post #9 was wrong
View attachment 182645
In the real circuit, cp should be tuned to compensate for inductor winding and PCB capacitance.
Also checked it in GENESYS and it tracks the LTSpice plotSurprizing. I'll check your .asc files tomorrow. Only one of the contradicting results can be correct
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