Abstract: Provided herein are apparatus and methods for reducing supply noise conversion to phase noise. In certain configurations, voltage controlled elements such as varactors are used to control a VCO output frequency. A VCO transfer function relating supply voltage noise to a common node of a varactor gives rise to a transfer function of value a representing a push coefficient. An intentional amount of supply noise can be added to a tuning voltage by injecting it at a tuning port of the VCO. By splitting an integration capacitance in a loop filter, an integration capacitance can be divided among a capacitor divider to create a transfer function of value ? representing a compensating coefficient. The injected noise from the capacitor divider can reduce VCO pushing by canceling the value ?. When the value ? is set equal to the value ?, the VCO pushing can be reduced to within the estimation or measurement accuracy of the value ?.

Abstract: A plurality of inductance enhanced interweaved rotary traveling wave oscillators (RTWO) is disclosed. Portions of the transmission line conductors are increased in length and run in parallel. Because the currents in these portions travel in the same direction, the inductance of these inductors is increased. By controlling the length of the transmission line conductors in these areas compared to the lengths where the currents in the oscillators travel in opposite directions, the overall impedance of the oscillators can be increased. Increased impedance leads to lower power and lower phase noise for the oscillators. Additionally, the interweaved oscillators are phase-locked to each other.

Abstract: A negative resistance device for a multiphase oscillator is disclosed. The negative resistance device is coupled to taps of the multiphase oscillator so that it injects no energy into the oscillator when the oscillator is most sensitive to noise, thereby decreasing the phase noise of the oscillator. The negative resistance device also guarantees the direction of movement of a traveling wave past the taps of the multiphase oscillator.

Abstract: A pulse width modulator based on a pair of rotary traveling wave oscillators. The first oscillator operates freely or as part of a phase-locked loop. The second oscillator operates at the same frequency as the first oscillator, but with a controllable phase offset from the first oscillator. The phase offset is set by an input voltage. A block takes the outputs of the first and second oscillators and combines them so that the output is a pulse whose width is the overlap of the oscillation signals from the first and second oscillators. The output pulse width is thus a function of the input voltage. When the pulse width modulator receives the input voltage from the output of a switching power supply, it can use the modulated pulse width to control the switching transistor of the power supply to maintain the output at a regulated voltage.

Abstract: A negative resistance device for a multiphase oscillator is disclosed. The negative resistance device is coupled to taps of the multiphase oscillator so that it injects no energy into the oscillator when the oscillator is most sensitive to noise, thereby decreasing the phase noise of the oscillator. The negative resistance device also guarantees the direction of movement of a traveling wave past the taps of the multiphase oscillator.

Abstract: A pulse width modulator based on a pair of rotary traveling wave oscillators. The first oscillator operates freely or as part of a phase-locked loop. The second oscillator operates at the same frequency as the first oscillator, but with a controllable phase offset from the first oscillator. The phase offset is set by an input voltage. A block takes the outputs of the first and second oscillators and combines them so that the output is a pulse whose width is the overlap of the oscillation signals from the first and second oscillators. The ouput pulse width is thus a function of the input voltage. When the pulse width modulator receives the input voltage from the output of a switching power supply, it can use the modulated pulse width to control the switching transistor of the power supply to maintain the output at a regulated voltage.

Abstract: A plurality of inductance enhanced interweaved rotary traveling wave oscillators (RTWO) is disclosed. Portions of the transmission line conductors are increased in length and run in parallel. Because the currents in these portions travel in the same direction, the inductance of these inductors is increased. By controlling the length of the transmission line conductors in these areas compared to the lengths where the currents in the oscillators travel in opposite directions, the overall impedance of the oscillators can be increased. Increased impedance leads to lower power and lower phase noise for the oscillators. Additionally, the interweaved oscillators are phase-locked to each other.