So why does that work as opposed to the whole PFFB from the TI document? Also, would that provide enough stability for global feedback?
Why specifically a balanced signal? Do you mean just differential or specifically balanced?
Found it between my ears some day.
Fact is, that I found no sim model otherwise so tried to do a very basic modelling from what is published in the data sheet.
Hardware tests showed that these simulations were surprisingly close to reality.
Finding the final values for compensation is just a game of trial and error.
Btw I guess the then TI designers did some empirical experiments as well without really in-depth modelling.
I presented my results to one of them and he gave a positive feedback at the time.
I assume that a SE-configuration would work similarly.
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It should be mentioned that my specific approach strictly emphasizes on frequency/square wave response.
Neither does it improve THD nor S/N as the TI app note does.
Neither does it improve THD nor S/N as the TI app note does.
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It is just a different approach. I do not care much about increasing THD and S/N but stress on taming the output series resonant tank -
without the zobel network.
Should we disable the existing stock TI Zobel for your cap feedback scheme to work? I wired one up on my old first gen TPA3116 amp (layout by member DUG) from 13 years ago (which has a Zobel per the TI datasheet recommendation). Tried listening to it and noticed some distortion on bass peaks and wondering if it is interacting with the existing Zobel? Have not had a chance to look at a square wave response yet on a scope. I am using two 220pF 1000v film caps in series for 110pF. My input coupling cap is a 1uF 100v film cap underneath the RCA, hence I jumpered the onboard 1uF ceramic cap.
As in-depth information of these chips is not available, we have to do real experiments to verify designs.
Consequently my approach is not to be considered final wisdom - but a step one can take to explore.
To answer your questions I attach my TPA3118 design I use practically for some years in my Li-ion battery powered guitar amps.
Please keep in mind that these modules are designed to be driven by an AFE with 2x2k2 output impedance as part of the compensating network.
With inputs open this board will oscillate wildly and shut down.
Consequently my approach is not to be considered final wisdom - but a step one can take to explore.
To answer your questions I attach my TPA3118 design I use practically for some years in my Li-ion battery powered guitar amps.
Please keep in mind that these modules are designed to be driven by an AFE with 2x2k2 output impedance as part of the compensating network.
With inputs open this board will oscillate wildly and shut down.
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Actually this really helps me in terms of simulation to see what works. I did a bit of a design switch, but with this info I may switch back. As long as the circuit will be stable, the rest should fall right into place.
I think I need to do this sometime down the line. I do love my little orange dark terror, and modeling like with something from kemper is awesome and all, but there's just something about good ole analog that's pleasing to the ears.