Abstract: Circuits, systems, and methods for generating a variable oscillator output. The circuits generally comprise a capacitor configured to receive first and second currents of a first polarity (e.g., charging currents) and a third current of a second polarity opposite to the first polarity (e.g., a discharge current). The circuit further comprises a first circuit configured to receive a bias input, a second circuit configured to receive a coarse control input, and a third circuit configured to receive a fine control input. The first circuit is further configured to provide the first current in response to the bias input. The second circuit is further configured to provide the second current in response to the coarse control input, such that the second current generally has a magnitude of from zero to a multiple of the magnitude of the first current.

Abstract: Circuits, systems, and methods for generating a variable oscillator output. The circuits generally comprise a capacitor configured to receive first and second currents of a first polarity (e.g., charging currents) and a third current of a second polarity opposite to the first polarity (e.g., a discharge current). The circuit further comprises a first circuit configured to receive a bias input, a second circuit configured to receive a coarse control input, and a third circuit configured to receive a fine control input. The first circuit is further configured to provide the first current in response to the bias input. The second circuit is further configured to provide the second current in response to the coarse control input, such that the second current generally has a magnitude of from zero to a multiple of the magnitude of the first current.

Abstract: Circuits and methods for generating an oscillator output. The circuit generally includes a ring oscillator, with a series of inverters connected in series and an LC resonator tank (or a variable resistance) coupled to the input and output of the inverter series. The method generally includes the steps of applying an operating voltage to such a circuit and generating an oscillator signal. The circuits and methods may be employed as a VCO component of a phase-locked loop. The upper limit of the oscillator signal frequency may be configured by altering or controlling the variable resistance and/or one or more parameters of the LC resonator tank. The circuit design demonstrates a high tolerance to variations in circuit or circuit component values.

Abstract: A differential output driver capable for selectively switching from an emphasis mode, a non-emphasis mode, and an idle state uses one pull-up device and two pull-down devices per output lead. The pull-up device is preferably always activated, and one or the other or both or neither of the pull-down devices are selectively activated to provide a desired behavior. Neither pull-down device is strong enough to singularly overcome the pull-up device and fully pull down an output lead to an emphasis logic low level. One of the pull-down devices is singularly strong enough to bring an output lead to a non-emphasis logic low level, which is higher than an emphasis logic low level. The other pull-down device is singularly strong enough to pull an output line from an emphasis logic high level to a non-emphasis logic high level. Working together, however, both devices can pull-down an output lead to an emphasis logic low level.

Abstract: Circuits and methods for generating an oscillator output. The circuit generally includes a ring oscillator, with a series of inverters connected in series and an LC resonator tank (or a variable resistance) coupled to the input and output of the inverter series. The method generally includes the steps of applying an operating voltage to such a circuit and generating an oscillator signal. The circuits and methods may be employed as a VCO component of a phase-locked loop. The upper limit of the oscillator signal frequency may be configured by altering or controlling the variable resistance and/or one or more parameters of the LC resonator tank. The circuit design demonstrates a high tolerance to variations in circuit or circuit component values.

Abstract: A differential output driver capable for selectively switching from an emphasis mode, a non-emphasis mode, and an idle state uses one pull-up device and two pull-down devices per output lead. The pull-up device is preferably always activated, and one or the other or both or neither of the pull-down devices are selectively activated to provide a desired behavior. Neither pull-down device is strong enough to singularly overcome the pull-up device and fully pull down an output lead to an emphasis logic low level. One of the pull-down devices is singularly strong enough to bring an output lead to a non-emphasis logic low level, which is higher than an emphasis logic low level. The other pull-down device is singularly strong enough to pull an output line from an emphasis logic high level to a non-emphasis logic high level. Working together, however, both devices can pull-down an output lead to an emphasis logic low level.