A fiber optic receiver that includes an opto-electronic transducer, an adjustable
response preamplifier circuit, and a post-amplifier circuit is described. The opto-electronic
transducer is configured to generate an electrical data signal in response to a
received optical data signal. The adjustable response preamplifier circuit is coupled
to the opto-electronic transducer and is operable to amplify an electrical data
signal generated by the opto-electronic transducer. The post-amplifier circuit
is coupled to an output of the preamplifier circuit and is configured to transmit
a mode control signal to the preamplifier circuit in response to a received control
signal. By transmitting the mode control signal from the post-amplifier to the
preamplifier, the adjustable response amplifier may be placed in the preamplifier
stage within a receiver optical sub-assembly (ROSA). As a result, the fiber optic
receiver may accommodate multiple operating modes (e.g., multiple bandwidth and
power operating modes) while conforming to existing receiver optical sub-assembly
(ROSA) size and pin count constraints.
