IR detector - logic outputs?

I am using a pulse frequency modulation circuit to create a FM square wave output as shown for a voice intercom (say 40Khz) output to an IR LED. I want to use an off shelf IR detector to detect the IR but it seems they all have logic outputs, can I use the FM signal??? - I want the input signal from the phototransistor to be input into a PLL for FM demodulation. How can I achieve this?

Also I was wondering how else i could convert from IR FM to audio?? Ive tried the 567 it doesn't seem to work too well

Any help would be appreciated!!