Adiabatic MOS oscillators

• US 5,483,207 A
• Filed: 12/30/1994
• Issued: 01/09/1996
• Est. Priority Date: 12/30/1994
• Status: Expired due to Term

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Gabara, Thaddeus J.
• Primary Examiner(s): MIS, DAVID C
• Application Number:
  US08/367,525
• Time in Patent Office: 375 Days
• Field of Search: 331/36 L, 331/45, 331/57, 331/60, 331/103, 331/117 R, 331/117 FE, 331/173, 331/181, 331/DIG. 3, 257/531, 327/566
• US Class Current: 331/117.0FE
• CPC Class Codes: H01F 2021/125 Printed variable inductor with taps, e.g. for VCO
• CPC Class Codes: H01L 27/0688 Integrated circuits having a three-dimensional layout
• CPC Class Codes: H03B 2201/0216 the means being an element with a variable inductance
• 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 5/1228 the amplifier comprising one or more field effect transistors
• CPC Class Codes: H03B 5/1256 the means comprising a variable inductance
• CPC Class Codes: Y10S 331/03 Logic gate active element oscillator

Abstract

High-frequency, low-power CMOS oscillators having electrically-tunable tank circuits are disclosed. Electrically-tunable inductors assure highly efficient oscillator operation and can be adjusted after manufacture to assure high yields of high-precision oscillator circuits.

Claims

1. An electrically-tunable inductor element, said element comprising:

an inductor element; and

a transistor having a charge inversion area electro-magnetically linked to said inductor element, whereby the inductance of said inductor element can be varied by varying the voltage applied to the transistor gate.

2. An electrically-tunable inductor element, said element comprising:

an inductive metalization element; and

a transistor having a charge inversion area electro-magnetically linked to a portion of said inductor element, whereby a portion of the inductance of said inductor element can be varied by varying the voltage applied to the transistor gate.

3. An MOS oscillator device having a tank circuit, said tank circuit comprising:

an element providing capacitance; and

an electrically-tunable inductor device, said device having--an inductor element and a transistor having a charge inversion area electro-magnetically linked to said inductor element, whereby the resonant frequency of said tank can be reactively tuned.