Oscillator with adjustable frequency

摘要

A circuit may include a delay element, a voltage adjust line, and a controllable capacitance. The delay element may have a delay and may include an input and an output. The input may be coupled to the output. The voltage adjust line may be configured to provide an adjusting voltage to the delay element to adjust the delay of the delay element. The controllable capacitance may be coupled to the output of the delay element and may be configured such that a change of the controllable capacitance adjusts the delay of the delay element.

主权项

1. A circuit comprising:
a delay element having a delay and including an input and an output, the input being coupled to the output; a voltage adjust line configured to provide an adjusting voltage to the delay element to provide fine-adjusting of the delay of the delay element; and a controllable capacitance coupled to the output of the delay element, the controllable capacitance configured such that a change of the controllable capacitance provides coarse-adjusting of the delay of the delay element, wherein the course-adjusting of the delay of the delay element by the controllable capacitance results in discrete delays with a first delay being between two adjacent discrete delays, the fine-adjusting of the delay of the delay element by the adjusting voltage results in a range of delays with a range greater than the first delay, and the change of the controllable capacitance is independently adjustable from a change in the adjusting voltage.