Abstract: Disclosed is a circuit having a high speed laser driver circuit, a semiconductor laser electrically connected to the high speed laser driver circuit, and an adjustable termination circuit electrically connected between the high speed laser driver circuit and the semiconductor laser, where the adjustable termination circuit is configured to control an output impedance seen by the semiconductor laser as a function of an input current provided to the adjustable termination circuit.

Abstract: Disclosed is a circuit having a high speed laser driver circuit, a semiconductor laser electrically connected to the high speed laser driver circuit, and an adjustable termination circuit electrically connected between the high speed laser driver circuit and the semiconductor laser, where the adjustable termination circuit is configured to control an output impedance seen by the semiconductor laser as a function of an input current provided to the adjustable termination circuit.

Abstract: The present disclosure provides a clock data recovery circuit that includes a phase locked loop unit, a delay locked loop unit and digital clock data recovery unit. The phase locked loop unit generates a clock signal based on a reference signal. The delay locked loop unit receives the clock signal from the phase locked loop, divides the clock signal into a plurality of clock signals and outputs the clock signals. The digital clock data recovery unit receives an input current signal, estimates a frequency of the input current signal, outputs a reference signal having the frequency, which can be transmitted to the phase locked loop unit, receives the clock signals from the delay locked loop, aligns a phase of the input current signal based on the clock signals and outputs an aligned current signal.

Abstract: The present disclosure provides a clock data recovery circuit that includes a phase locked loop unit, a delay locked loop unit and digital clock data recovery unit. The phase locked loop unit generates a clock signal based on a reference signal. The delay locked loop unit receives the clock signal from the phase locked loop, divides the clock signal into a plurality of clock signals and outputs the clock signals. The digital clock data recovery unit receives an input current signal, estimates a frequency of the input current signal, outputs a reference signal having the frequency, which can be transmitted to the phase locked loop unit, receives the clock signals from the delay locked loop, aligns a phase of the input current signal based on the clock signals and outputs an aligned current signal.

Abstract: Various circuit techniques to implement continuous-time filters with improved performance are disclosed. The present invention uses RMC type integrators that exhibit lower harmonic distortion. In one embodiment, a novel high-gain two-pole operational amplifier is used along with RMC architecture to achieve lower harmonic distortion. In another embodiment, the present invention uses dummy polysilicon resistors to accurately compensate for the distributed parasitics of the polysilicon resistors used in RMC integrator. In yet another embodiment, the present invention provides an on-chip tuner with a differential architecture for better noise immunity.