A telecommunications system and constituent integrated circuit that
includes a post-amplifier assembly configured for communication with an
optical receiver, a laser driver assembly configured for communication
with the optical transmitter, and a controller assembly configured to
control the post-amplifier and laser driver. The post-amplifier, the
laser driver, and the controller assemblies are embodied on a single
integrated circuit, thereby reducing manufacturing costs. Noise due to
clock generation may be reduced by having the clock act on a transient
basis, turning on when needed during the boot process, and turning off
when not needed during normal operation.