Low power local oscillator

A local oscillator device comprising:

• an oscillator module having a first inductive element and a capacitive element coupled in parallel with the first inductive element;
• a frequency divider coupled to the oscillator module and configured to deliver a local oscillator signal;
• and
• an autotransformer comprising the first inductive element, a second inductive element, and a third inductive element, a first terminal of the second inductive element DC coupled to a first terminal of the first inductive element, a second terminal of the second inductive element being a first output terminal of the autotransformer, a first terminal of the third inductive element DC coupled to a second terminal of the first inductive element, a second terminal of the third inductive element being a second output terminal of the autotransformer, the first output terminal and the second output terminal of the autotransformer being DC coupled to input terminals of the frequency divider, wherein the first inductive element comprises a first flat conductive track having an interlaced coil shape, and the second and third inductive elements each comprises respective second and third flat conductive track each having a coil shape, the second and third conductive tracks being interlaced with each other and located on a periphery of the first inductive element.

A local oscillator device comprising:

• an oscillator module having a first inductive element and a capacitive element coupled in parallel with the first inductive element;
• a frequency divider coupled to the oscillator module and configured to deliver a local oscillator signal;
• and
• an autotransformer comprising the first inductive element, a second inductive element, and a third inductive element, a first terminal of the second inductive element DC coupled to a first terminal of the first inductive element, a second terminal of the second inductive element being a first output terminal of the autotransformer, a first terminal of the third inductive element DC coupled to a second terminal of the first inductive element, a second terminal of the third inductive element being a second output terminal of the autotransformer, the first output terminal and the second output terminal of the autotransformer being DC coupled to input terminals of the frequency divider, wherein the frequency divider is configured to divide a frequency of an input signal at the first output terminal and the second output terminal of the autotransformer, wherein the oscillator module is configured to generate an oscillating signal with an amplitude below a threshold amplitude on terminals of the first inductive element, and the autotransformer is configured to generate the input signal with an amplitude above the threshold amplitude.

A transceiver system comprising:

• an antenna configured to transmit and receive radio frequency signals,
• a transmitting stage coupled to the antenna;
• a receiving stage coupled to the antenna;
• and
• a local oscillator device coupled to the transmitting stage and the receiving stage, the local oscillator device comprising:
• an oscillator module having a resonator that comprises a first inductive element and a capacitive element coupled in parallel with the first inductive element;
• a frequency divider coupled to the oscillator module and configured to generate a local oscillator signal;
• and
• an autotransformer comprising the first inductive element, a second inductive element, and a third inductive element, a first terminal of the second inductive element DC coupled to a first terminal of the first inductive element, a second terminal of the second inductive element being a first output terminal of the autotransformer, a first terminal of the third inductive element DC coupled to a second terminal of the first inductive element, a second terminal of the third inductive element being a second output terminal of the autotransformer, the first output terminal and the second output terminal of the autotransformer being DC coupled to input terminals of the frequency divider.

A method comprising:

• generating a first oscillating signal across a first inductive element, the first oscillating signal having a first amplitude, the first inductive element coupled in parallel with a capacitive element to form a resonator;
• generating a second oscillating signal with an autotransformer, the second oscillating signal having a second amplitude bigger than the first amplitude, wherein the autotransformer comprises the first inductive element, a second inductive element, and a third inductive element, a first terminal of the second inductive element DC coupled to a first terminal of the first inductive element, a second terminal of the second inductive element being a first output terminal of the autotransformer, a first terminal of the third inductive element DC coupled to a second terminal of the first inductive element, a second terminal of the third inductive element being a second output terminal of the autotransformer, the first output terminal and the second output terminal of the autotransformer being DC coupled to input terminals of a frequency divider;
• and
• generating a local oscillator signal with the frequency divider, the local oscillator signal having a frequency based on the second oscillating signal.