Dual-Mode Voltage Controlled Oscillator Using Integrated Variable Inductors
Conventionally, frequency tuning is achieved by changing the capacitance of a tank using varactor. However, it is more power efficient to minimize the capacitance of the tank and adjust the inductance for frequency variation. Therefore, the need for a variable inductor arises.
A novel integrated variable inductor using an on-chip transformer together with a variable capacitor has been developed. The variable capacitor is connected to the secondary coil of the transformer. By changing the capacitance at the secondary coil of the transformer, the equivalent inductance looking into the primary coil of the transformer can be adjusted.
In this new design, the frequency tuning range can be extended to be much larger than that can be achieved with existing solution with variable capacitors.
With such variable inductor, the capacitor can be fixed and be small so that all the parameters including frequency tuning range, phase noise, and power consumption, can be greatly improved. It has also been applied to a VCO to achieve wide frequency tuning range and high performance that are not achievable with existing technologies.
1. Compared to capacitive tuning, the inductive tuning gives rise to a wider frequency tuning range, smaller chip area, lower phase noise and lower power consumption
2. It is possible to improve performance of many high-frequency integrated circuits and systems
3. It operates at a lower cost
- All high-frequency integrated circuits (ICs) and systems that require inductors and frequency tuning, for example, high-frequency LC oscillators, phase-locked loop, frequency synthesizers
- Any other high-frequency wireless or optical communication systems
Patent Number: US7268634B2
Application Number: US2004927785A
Inventor: Luong, Howard Cam | Leung, Lai Kan
Priority Date: 27 Aug 2004
Priority Number: US7268634B2
Application Date: 27 Aug 2004
Publication Date: 11 Sep 2007
IPC Current: H03J000702
US Class: 331036L | 331181
Assignee Applicant: The Hong Kong University of Science & Technology
Title: Dual-mode voltage controlled oscillator using integrated variable inductors
Usefulness: Dual-mode voltage controlled oscillator using integrated variable inductors
Summary: Used in a voltage controlled oscillator (claimed) which is used in a wireless transceiver, multiple-band application and wide band application.
Novelty: Variable inductor for use in voltage controlled oscillator, has capacitor providing variable capacitance in parallel with secondary coil of transformer for tuning equivalent inductance on primary coil
電子
電路設計
27 Aug 2004
US 7268634
TTC.PA.191
香港
