Data signal threshold detection and/or recovery in optical and/or optoelectric receivers and/or transceivers

An optical receiver, comprising:

• a photodiode configured to receive an optical signal and provide an electrical signal;
• a first circuit having a first time constant and receiving the electrical signal;
• a second circuit having (i) a common input and a common output with said first circuit and (ii) a second time constant, said second time constant being substantially less than said first time constant and allowing a common-mode voltage thereon to decay or change at a faster rate than the first circuit, wherein the common-mode voltage can have a value greater than an amplitude of the electrical signal;
• a switch configured to (i) charge said first circuit with the electrical signal when the switch is in a first state, and (ii) charge or discharge said second circuit when the switch is in a second state, the switch having the second state when said electrical signal is no longer received at said common input;
• and
• logic configured to place said switch in the first state whenever said electrical signal is received at said common input for an entire duration of said electrical signal, place said switch in the second state when said electrical signal is not received at said common input, and determine a decision threshold for binary logic states of the electrical signal received by the detection circuit based on the common-mode voltage.