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  1. K

    Class D Amplifiers 101

    Post 80?
  2. K

    Class D Amplifiers 101

    A suitable inductor can be ED0006 AL from Coilcraft
  3. K

    Class D Amplifiers 101

    Here is 10ns dt and 2Mhz Fs. The pair kinks got merged to make a smooth zero transition, only each polarity now is lacking an offset as the distortion is about 0.5%. The feedback can operate now much better in the lack of abrupt kinks, as the frequency is high 60db NFB can be easily applied to...
  4. K

    Class D Amplifiers 101

    It looks like the dt correction is voltage sense as it is optimized for 3ohms load.
  5. K

    Class D Amplifiers 101

    What makes the amp better sounding at high switching frequencies is the very low ripple current. The kinks observed are separated by PP current of the ripple, running it at 2Mhz the the kinks will have shorter separation acting at very low power, very similar to under biased class AB. There the...
  6. K

    Class D Amplifiers 101

    I tried out my idea on post 62 to see the feasibility. I simulate it at standard 400khz and 50ns dt. This is without correction. The distortion. A roughly adjusted gives distortion.
  7. K

    Class D Amplifiers 101

    This is 1khz modulating 2Mhz with 50ns dead time with the current of the inductor. Remark that the flat occurs when the peak current crosses the 0A.
  8. K

    Class D Amplifiers 101

    This is the TI patent used in TPA32XX series. https://patents.google.com/patent/US7795970B2/en @cmj2017 The dead time provokes nonlinear transfer function independent from the input frequency. You get a pair of flat on every zero crossing even with 0.001Hz. Google dead time class d.
  9. K

    Class D Amplifiers 101

    I did not invent the class d amplifiers. https://www.infineon.com/dgdl/an-1071.pdf?fileId=5546d462533600a40153559538eb0ff1 page 9-11
  10. K

    Class D Amplifiers 101

    Thank you for posting a user's introduction for class D . If you read the IRF tutorial you can see there is much more to talk about. The output inductance has a ripple current of triangular shape with peak current alternating positive and negative at 50% DT. When both switches go off for dead...
  11. K

    Class D Amplifiers 101

    Hello Don, I truly appreciate this thread you have started it, at on stop and someone has all he needs to know about class D. In 1979 a colleague in R&D department built a class D amp from the Hitachi MOSFET databook for portable guitar amp, It had so screaming sound that made disgust from this...
  12. K

    Class D Amplifiers 101

    I just started learning about class D amp design attracted by GaN transistors. My only experience with such amps is few years ago I tried out the TPA3116D2 in PBTL board. I recorded the horrifying sound while I took refuge on the balcony and posted here I modified the amp by passing the Fs from...
  13. K

    Class D Amplifiers 101

    How self oscillating nature kills the dead time distortion? This is the linearity of 2.1Mhz double pole feedback amp MS thesis presented in this thread This anomaly can be measured by IM 50hz and 20khz where the ZVS/HD crossing provokes slew rate saturation, and the 20khz gets blanked...
  14. K

    Class D Amplifiers 101

    I want to add on this reference thread the dead time issue in class D amplifiers. The dead time is necessary to switch safely on transitions, both upper and lower switches go off the time the drivers delay difference and the switching transistors toggle. Nowadays the fastest can be obtained by...
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