Operation of a LLC power converter is not spread spectrum, The circuit is LC resonant and the frequency varies between two region extremes, depending on the load ... (regions defined by LsC & (Ls+Lm)C)
AND8311/D "Understanding the LLC Structure in Resonant Applications": https://www.onsemi.com/pub/Collateral/AND8311-D.PDF
Analysis and Measurement of Resonant Tank Current on
LLC: https://www.ti.com/lit/pdf/slua690
High-performance resonant mode LLC controller:
https://www.ti.com/lit/gpn/ucc25600


AND8311/D "Understanding the LLC Structure in Resonant Applications": https://www.onsemi.com/pub/Collateral/AND8311-D.PDF
Analysis and Measurement of Resonant Tank Current on
LLC: https://www.ti.com/lit/pdf/slua690
High-performance resonant mode LLC controller:
https://www.ti.com/lit/gpn/ucc25600


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I have NanoVNA.
Scope only 100 MHz.....
Since your SMPS is resonant mode, & not hard switched, maybe there is less chance of VHF Oscillation, depending on the gate drive.
Is the GaN Clas D amplifier self resonating feedback or PWM
How to Effectively Measure High Performance eGaN FETs in Applications: https://epc-co.com/epc/Portals/0/epc/documents/application-notes/How2AppNote006 Measurement.pdf
Operation of a LLC power converter is not spread spectrum, The circuit is LC resonant and the frequency varies between two region extremes, depending on the load ... (regions defined by LsC & (Ls+Lm)C)
AND8311/D "Understanding the LLC Structure in Resonant Applications": https://www.onsemi.com/pub/Collateral/AND8311-D.PDF
Analysis and Measurement of Resonant Tank Current on
LLC: https://www.ti.com/lit/pdf/slua690
High-performance resonant mode LLC controller:
https://www.ti.com/lit/gpn/ucc25600
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Thank you for clearing this up with illustration.
F##King fantastic mate!! leave it on. please yourself, this is not a massive commercial endeavour that needs to censor. I have been waiting for someone on here to do something interesting with the EPC fets. I have a strip that I bought to try in a headphone amp EPC2012 IIRC. I think these are not so bad parts to be stuck with 🙂 i'm sorry if I have missed it, but do you have any idea of cost for a 2 channel all in one amp?
What boards do you currently have and what is coming up in production?
Looking for something around 50w to 75w per ch 4 ohm load.
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