Hi,
I have an issue with a DAC application. I am using the PCM4104 with a single op-amp buffer.
It is nearly the same as the reference circuit of the data sheet - but without the DC-blocking caps:
This circuit produces some high frequency oscillation (sine / discharging of some capacitance) - at around 100kHz - easily seen after the power amplifier (gain 21dB) level about 45mVpp.
The problem isn't there when the DC caps are inserted like the reference design shows.
The same problem occures with PCM3060 which I use in another application.
The reference design of PCM3060 does show the same differential capacitor-less LPF buffer as above.
Would it be possible to do this in stead:
And will this solve the problem?
Will the Vcom output of PCM4104 be capable of driving the Vcom of OPA1632?
/Robert