Low-power voltage-controlled oscillator
AssigneeTagArray, Inc.
InventorMohammad Ardehali
Life of this patent
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Abstract
In one embodiment, a voltage-controlled oscillator (VCO) is provided that includes: a plurality of differential inverters coupled to form a loop, each differential inverter having a differential pair of transistors configured to steer a tail current from a current source, the current source sourcing the tail current responsive to a bias voltage, wherein each transistor in the differential pair couples to a power source through a corresponding switching-capacitor circuit; and a bias circuit configured to generate the bias voltage such that a transconductance for each transistor in the differential pairs is proportional to a factor that is a function of a ratio of transistor widths within the bias circuit.
Claims20
A ring oscillator, comprising:
- a plurality of differential inverters coupled to form a loop, each differential inverter having a differential pair of transistors configured to steer a tail current from a current source, the current source sourcing the tail current responsive to a bias voltage;
- and
- a bias circuit configured to generate the bias voltage such that a transconductance for each transistor in the differential pairs is proportional to a factor that is a function of a ratio of transistor widths within the bias circuit.
A voltage-controlled oscillator (VCO), comprising:
- a plurality of differential inverters coupled to form a loop, each differential inverter having a differential pair of transistors configured to steer a tail current from a current source, the current source sourcing the tail current responsive to a bias voltage, wherein each transistor in the differential pair couples to a power source through a corresponding switching-capacitor circuit;
- and
- a bias circuit configured to generate the bias voltage such that a transconductance for each transistor in the differential pairs is proportional to a factor that is a function of a ratio of transistor widths within the bias circuit.
A phase-locked loop (PLL), comprising:
- a phase detector configured to compare the phase between a divided signal and in input signal to provided a phase detector output;
- a loop filter to filter the phase detector output to provide a tuning voltage;
- and
- A voltage-controlled oscillator (VCO) including a plurality of differential inverters coupled to form a loop, each differential inverter having a differential pair of transistors configured to steer a tail current from a current source, the current source sourcing the tail current responsive to a bias voltage, wherein each transistor in the differential pair couples to a power source through a corresponding switching-capacitor circuit having an adjustable capacitance responsive to the tuning voltage;
- and a bias circuit configured to generate the bias voltage such that a transconductance for each transistor in the differential pairs is proportional to a factor that is a function of a ratio of transistor widths within the bias circuit.
Dependencies are inferred from the claim text.