I want to make a digital phonometer with a Pic, i search a scheme for analog section from condenser microphone to analog pic input, with an operational at single supply
what's the signal at the pic input like? maybe you can make your question the way by giving the detailed spec with regard to the analog circuit you want, eg. the input signal, the output signal.
opamp with single supply circuit needs a ref voltage subcircuit to increase the 'ground' to a positive value. many docs can be found on the web about this.
the input signal must to be an electrect condenser microphone and the signal for the analog input of the pic must be comprise in 0-5V dc range, i have tested and simulate some circuit with operational in ideal reticfier configuration, but in single power supply i have always problem