Phase-locked loop

A phase-locked loop comprising:

• a detector;
• a filter connected to the detector;
• and
• a voltage controlled oscillator, wherein the voltage controlled oscillator comprises:
• a control input;
• an output terminal, wherein a signal derived from an output of the voltage controlled oscillator is passed to the detector;
• a voltage controller connected to the control input, wherein the control input is connected to the filter;
• an inductor and a first capacitor, connected in parallel, each comprising a first terminal and a second terminal, wherein respective first terminals of the inductor and the first capacitor are connected to the output terminal;
• a first resistor and a second resistor connected to the voltage controller;
• a second capacitor and a third capacitor, each comprising a third terminal and a fourth terminal, wherein the third terminal of the second capacitor is connected to the first resistor, the fourth terminal of the second capacitor is connected to the output terminal, the third terminal of the third capacitor is connected to the second resistor, and the fourth terminal of the third capacitor is connected to respective second terminals of the inductor and the first capacitor;
• and
• a first transistor and a second transistor, each comprising a fifth terminal, a sixth terminal and a control terminal, wherein the fifth terminal of the first transistor is connected to the output terminal, the sixth terminal of the first transistor is connected to the sixth terminal of the second transistor, the control terminal of the first transistor is connected to the second resistor and the third terminal of the third capacitor, the fifth terminal of the second transistor is connected to the fourth terminal of the third capacitor, and the control terminal of the second transistor is connected to the first resistor and the third terminal of the second capacitor.