I need an amplifier front end for my dsp audio and I'm wondering what exactly I should do.
I think the main use will be for a guitar effects processor but I think I'll also want something that processes audio in general(not sure if I need to make a distinction?).
I'll be using the PCM1804 for the ADC conversion and I'll be putting an amplifier front end on it to try and get the max resolution. (So, say, it will be calibrated to the input signal).
On the datasheet for the ADC it says the analog input voltage is -0.3V to (Vcc + 0.3V).
I'm not sure whats up with the -0.3V but in any case Vcc is from -0.3V to
6.5V.I think because of convience I'll be using Vcc at 5V and I'll want to minimize the power supply devices I'll need.
Now the op amps I've been looking at for audio say the min Vcc is 5V. I'm wondering if its a good idea to run at the min voltages?
Right now I need a power supplies of 3.3V for the DSP, ADC, and DAC; 5V for ADC and DAC and then the supplies with for the op amps(buffers, filters, and amplifiers). I'd like to use the same power supplies instead of creating a new one. I will of course need a negative rail also so I was hoping that all I need is 3.3V and +-5V but I'm a little worried about using the +-5V on the op amp since its the min supply voltage. Not sure if it will cause any problems?
Also, would there be any special considers I need to worry about for different types of inputs into the op amps? Are there better configurations than just the simple stuff you learn in any basic text book? (I was thinking of just using a fully differential op amp configured as an inverting amp)
Ultimately I rather not use the op amps if possible because it causes me to need to have a negative supply but maybe this isn't difficult with with some of the ic's available now days?
Is there any good books on audio circuits with mainly practical knowledge? I'm just really afraid of using some of the stuff I've learned from basic EE books and it not cutting it in the real world. (I do have the AOE which I need to re read again).
Thanks, Jon