Resonant driver apparatus and method

A method for forming a resonant driver for driving a load circuit at a resonant frequency, comprising the steps of:

• providing a bank of tunable components;
• providing a resonant driver circuit coupled to the bank of tunable components and to the load circuit;
• driving the load circuit with the resonant driver circuit with a signal at a frequency approximately equal to the resonant frequency;
• providing an external reference element;
• providing an internal reference element;
• providing a reference sensor coupled to the resonant driver circuit, to the external reference element, and to the internal reference element;
• determining a difference between the external reference element and the internal reference element with the reference sensor;
• providing a control circuit coupled to the reference sensor and to the bank of tunable components;
• and
• electronically tuning the bank of tunable components with the control circuit in response to the difference.

A liquid crystal display including a display circuit and harmonic driver for driving the display circuit at a resonant frequency, comprising:

• a tunable capacitor;
• a resonant driver circuit coupled to the tunable capacitor and to the display circuit, for driving the display circuit at approximately the resonant frequency;
• a power dissipation sensor coupled to the resonant driver circuit, for determining the power dissipation of the resonant driver circuit;
• and
• control logic coupled to the tunable capacitor and to the power dissipation sensor, for monitoring the power dissipation of the resonant driver circuit and for tuning the tunable capacitor in response to the power dissipation of the resonant driver circuit.

A display driver for driving a data column in a liquid crystal display with a video signal, the display driver comprising:

• a resonant clock circuit for providing a resonant clock signal having a time-dependent value;
• a sampling circuit for sampling the video signal to form a sampled signal having a sampled value;
• a comparator coupled to the resonant clock circuit and to the sampling circuit, the comparator for asserting a first signal when the time-dependent value is less than the sampled value, and for asserting a second signal when the time-dependent value is greater than sampled value;
• and
• a switch coupled to the resonant circuit, to the comparator, and to the data column, the switch for coupling the resonant circuit to the data column in response to the first signal, and for decoupling the resonant circuit from the data column in response to the second signal.

A method for driving a data column in a liquid crystal display with a video signal, the method comprising the steps of

• providing a resonant clock signal having a time-dependent value;
• sampling the video signal to form a sampled signal having a sampled value;
• comparing the time-dependent value to the sampled value;
• asserting a first signal when the time-dependent value is less than the sampled value;
• asserting a second signal when the time-dependent value is greater than sampled value;
• coupling the resonant clock signal to the data column in response to the first signal;
• and
• decoupling the resonant clock signal from the data column in response to the second signal.

A method for driving a display element with a resonant clock signal having a time-dependent value, the method comprising the steps of

• sampling a video signal to form a sampled value;
• comparing the time-dependent value to the sampled value;
• coupling the resonant clock signal to the data column when the time-dependent value is less than the sampled value;
• and
• decoupling the resonant clock signal from the data column when the time-dependent value is greater than sampled value.

An apparatus for converting a digital value to an analog value comprising:

• a resonant clock circuit for providing a resonant clock signal having a time-dependent value;
• a digital clock circuit for providing a digital clock signal having a time-dependent digital value responsive to the time-dependent value;
• a storage for storing the digital value;
• a comparator coupled to the digital clock circuit and to the storage, the comparator for asserting a first voltage signal when the digital value exceeds the time-dependent digital value and for asserting a second voltage signal when the time-dependent digital value exceeds the digital value;
• and
• a switch coupled to the resonant clock signal and to the comparator, the switch for coupling the resonant clock circuit to an output in response to the first voltage signal, and for decoupling the resonant clock circuit from the output in response to the second voltage signal.

A method for converting a digital value to an analog value, the method comprising the steps of:

• storing the digital value into a storage;
• providing a resonant clock signal having a time-dependent value and a digital clock signal having a time-dependent digital value responsive to the time-dependent value;
• comparing the time-dependent digital value to the digital value;
• asserting a first voltage signal when the digital value exceeds the time-dependent digital value;
• asserting a second voltage signal when the time-dependent digital value exceeds the digital value;
• coupling the resonant clock circuit to an output in response to the first voltage signal;
• and
• decoupling the resonant clock circuit from the output in response to the second voltage signal.

A method for converting a digital value to an analog value using a resonant clock circuit and a digital clock circuit, the resonant clock circuit including a resonant clock signal having a time-dependent value and the digital clock circuit including a digital clock signal having a time-dependent digital value responsive to the time-dependent value, the method comprising the steps of:

• comparing the time-dependent digital value to the digital value;
• coupling the resonant clock circuit to an output when the digital value exceeds the time-dependent digital value;
• and
• decoupling the resonant clock circuit from the output when the time-dependent digital value exceeds the digital value.