Ultra low power oscillator

A frequency generator embodied in an integrated circuit manufactured at a process node below 100 nm, the frequency generator comprising:

• current starved oscillator means for generating an output frequency signal in dependence on a voltage of a bias signal;
• and
• self-biased current generator means for generating said bias signal, wherein said self-biased current generator means comprises a first transistor and a second transistor connected in series, said bias signal being taken from a midpoint between said first transistor and said second transistor,
• and respective gates of said first and second transistors are connected to keep said first and second transistors in a cut-off state, such that said self-biased current generator means operates in a deep sub-threshold state and a current of said bias signal is dependent on a leakage current in said first and second transistors.

A method of generating an output frequency signal in a frequency generator embodied in an integrated circuit manufactured at a process node below 100 nm, the method comprising the steps of:

• providing a self-biased current generator arranged to generate a bias signal, wherein said self-biased current generator comprises a first transistor and a second transistor connected in series, said bias signal being taken from a midpoint between said first transistor and said second transistor,
• and respective gates of said first and second transistors are connected to keep said first and second transistors in a cut-off state;
• operating said self-biased current generator in a deep sub-threshold state to generate said bias signal, such that a current of said bias signal is dependent on a leakage current in said first and second transistors;
• and
• generating an output frequency signal in dependence on a voltage of said bias signal in a current starved oscillator.