Fully digital CMOS based optical receiver

A completely digital optical receiver is provided. The optical receiver includes a photodiode configured to provide a photodiode output responsive to an on-off keyed (OOK) optical input. Two or more digital inverters connected in series with each other are configured to receive the photodiode output and provide an amplified digital output. A digital clock and data recovery (CDR) circuit receives the amplified digital output and provides a clock output and a data output. A digital photodiode discharging circuit is connected to the photodiode and controlled by the clock output of the CDR circuit.