el00
Member level 5
Hello I need to drive 48Vrms into a few ohm speaker with a very short duty cycle (less than 10%) therefore with a low average power. In this application I am transmitting pre-recorded wav files. Frequency more or less is audio band.
I am interested in directly driving power mosfets from an FPGA, doing a similar thing to the class D amplifier, but without the need to convert WAV->DAC->classD. In fact, in this way, there is a double conversion to analog and then to digital because the class D de facto is a digital system.
I could not find any literature or documentation on this. The only thing that I found are those 2 commercial chips, which do not fit my requirements due to the low power and voltage rails:
TAS3251: this is, however, not exactly what I am talking about, since it contains a DSP and DAC's, converting the signal to analog an back to digital. Why this waste of resources? Why not drive the final stage directly?
BM28723MUV: this is exactly what I want to do. However, it would have been nice if the FET's were external, so that I can use whatever power device I want to increase the power.
Other than that, I could not find anything else.
I can develop it, but I have very little experience with class D. Is there any reading that you suggest?
I am interested in directly driving power mosfets from an FPGA, doing a similar thing to the class D amplifier, but without the need to convert WAV->DAC->classD. In fact, in this way, there is a double conversion to analog and then to digital because the class D de facto is a digital system.
I could not find any literature or documentation on this. The only thing that I found are those 2 commercial chips, which do not fit my requirements due to the low power and voltage rails:
TAS3251: this is, however, not exactly what I am talking about, since it contains a DSP and DAC's, converting the signal to analog an back to digital. Why this waste of resources? Why not drive the final stage directly?
BM28723MUV: this is exactly what I want to do. However, it would have been nice if the FET's were external, so that I can use whatever power device I want to increase the power.
Other than that, I could not find anything else.
I can develop it, but I have very little experience with class D. Is there any reading that you suggest?