Voltage controlled oscillator
AssigneeNEC Electronics Corporation
InventorTooru Shibata
Life of this patent
Estimating the term…
Abstract
A voltage controlled oscillator includes an LC resonance circuit having an inductance and a voltage dependent variable capacitance connected in parallel between first and second output terminals; a transistor pair circuit connected in parallel with the LC resonance circuit between the first and second output terminals and having negative conductance to keep oscillation of the LC resonance circuit; a resistance having one end connected with the oscillation transistor pair circuit; and a current source connected with the other end of the resistance.
Claims20
A voltage controlled oscillator comprising:
- an LC resonance circuit having an inductance and a voltage dependent variable capacitance connected in parallel between first and second output terminals;
- a transistor pair circuit connected in parallel with said LC resonance circuit between said first and second output terminals and having negative conductance to keep oscillation of said LC resonance circuit;
- a resistance having one end connected with said oscillation transistor pair circuit;
- and
- a current source connected with the other end of said resistance.
A voltage controlled oscillator comprising:
- an LC resonance circuit provided between first and second output terminals and having two inductances connected in series and two capacitances connected in series, wherein the series-connected capacitances are connected in parallel to the series-connected inductances, a power source voltage is supplied to a node between the two inductances, and a control voltage is supplied to a node between the two capacitances to vary a capacitance;
- a transistor pair circuit connected in parallel with said LC resonance circuit between said first and second output terminals and having negative conductance to keep oscillation of said LC resonance circuit;
- a resistance having one end connected with said transistor pair circuit;
- and
- a current source connected between the other end of said resistance and a ground voltage.
A voltage controlled oscillator comprising:
- an LC resonance circuit provided between first and second output terminals and having two inductances connected in series and two capacitances connected in series, wherein the series-connected capacitances are connected in parallel to the series-connected inductances, and a control voltage is supplied to a node between the two capacitances to vary a capacitance;
- a first transistor pair circuit connected in parallel with said LC resonance circuit between said first and second output terminals and having negative conductance to keep oscillation of said LC resonance circuit;
- a second transistor pair circuit provided between said first and second output terminals on an opposite side to said first transistor pair circuit with respect to said LC resonance circuit, connected in parallel with said LC resonance circuit and having negative conductance to keep oscillation of said LC resonance circuit;
- a resistance having one end connected with said first transistor pair circuit;
- and
- a current source connected between the other end of said resistance and a first voltage,
- wherein said second transistor pair circuit is connected to a second voltage.
Dependencies are inferred from the claim text.