Inductor unit and oscillator using the inductor unit

• US 20060232348A1
• Filed: 04/12/2006
• Published: 10/19/2006
• Est. Priority Date: 04/19/2005
• Status: Abandoned Application

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Hino, Takuo
• Application Number:
  US11/403,048
• Publication Number:
  US 20060232348A1
• Time in Patent Office: Days
• US Class Current: 331/167
• CPC Class Codes: H03B 5/1215 the current source or degeneration circuit being in common to both transistors of the pair, e.g. a cross-coupled long-tailed pair
• CPC Class Codes: H03B 5/1231 the amplifier comprising one or more bipolar transistors
• CPC Class Codes: H03B 5/1243 the means comprising voltage variable capacitance diodes
• CPC Class Codes: H03B 5/1265 switched capacitors
• CPC Class Codes: H03B 5/1271 the frequency being controlled by a control current, i.e. current controlled oscillators

Abstract

Functionality and performance of a voltage-controlled oscillator are improved by continuously controlling inductor output by a control signal. Having a first inductor, a current detection circuit that detects current flow to the first inductor, a current source 4 for generating a current signal based on the detected current, and a second inductor to which the current signal is applied, the first inductor and second inductor are disposed to a predetermined magnetically coupled position for setting the inductance of the first inductor as desired.

Claims

1. An inductor unit comprising:

a first inductor;

a current signal generator operable to detect an electric signal denoting current flowing to the first inductor or the voltage at both ends of the first inductor, and to generate a current signal based on the electric signal; and

a second inductor that receives the current signal;

wherein the first inductor and second inductor are disposed to a predetermined magnetically coupled position and the inductance of the first inductor is set desirably.

2. The inductor unit described in claim 1, further comprising:

a control signal generator operable to generate a control signal;

wherein the current signal generator controls the amplitude of the current signal based on the control signal.

3. The inductor unit described in claim 1, wherein:

the first inductor is a spiral-shaped strip conductor formed on a first layer; and

the second inductor is a spiral-shaped strip conductor formed on a second layer.

4. The inductor unit described in claim 3, further comprising an insulation layer between the first layer and second layer.

5. The inductor unit described in claim 3, wherein the first layer and second layer are formed on a semiconductor substrate.

6. The inductor unit described in claim 5, wherein the second layer is formed on the semiconductor layer, and the first layer is formed above the second layer.

7. The inductor unit described in claim 1, wherein the first inductor and second inductor are spiral-shaped strip conductors formed on the same layer.

8. The inductor unit described in claim 7, wherein the first inductor and second inductor are formed on a semiconductor substrate.

9. An oscillator comprising:

an inductor unit comprising

a first inductor;

a current signal generator operable to detect an electric signal denoting current flowing to the first inductor or the voltage at both ends of the first inductor, and to generate a current signal based on the electric signal; and

a second inductor that receives the current signal;

wherein the first inductor and second inductor are disposed to a predetermined magnetically coupled position and the inductance of the first inductor is set desirably; and

a variable capacitance device connected to the inductor unit;

wherein the oscillator oscillates at an oscillation frequency determined by the inductance of the inductor unit and the capacitance of the variable capacitance device.

10. The oscillator described in claim 9, further comprising:

one or more fixed capacitors removably connected to the variable capacitance device;

wherein the oscillator oscillates at an oscillation frequency determined by the inductance of the inductor unit and the capacitance of the variable capacitance device and the fixed capacitor.

11. The oscillator described in claim 9, further comprising:

a control signal generator operable to generate a control signal;

wherein the current signal generator controls the amplitude of the current signal based on the control signal.

12. The oscillator described in claim 11, wherein:

the control signal generator generates a frequency band signal denoting information operable to switch between a plurality of frequency bands; and

the current signal generator controls the amplitude of the current signal based on the frequency band signal.

13. The oscillator described in claim 11, wherein:

the control signal generator generates a capacitance control signal denoting the voltage at both ends of the variable capacitance device; and

the current signal generator controls the amplitude of the current signal based on the capacitance control signal.

14. The oscillator described in claim 11, wherein:

the control signal generator generates a temperature characteristic signal denoting change in capacitance due to temperature based on at least one of the variable capacitance device and the fixed capacitor; and

the current signal generator controls the amplitude of the current signal based on the temperature characteristic signal.

15. The oscillator described in claim 14, further comprising:

a temperature sensor operable to measure the temperature of at least one of the variable capacitance device and the fixed capacitor; and

a storage circuit operable to store the temperature characteristic signal;

wherein the storage circuit generates the temperature characteristic signal based on the temperature measured by the temperature sensor.

16. The oscillator described in claim 15, wherein the temperature characteristic signal denotes the change in capacitance due to temperature and the capacitance control signal.