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Tunable high-Q resonator by general impedance converter
Toshiro Mifune1, Todor M Mishonov1, Nikola S Serafimov1
1Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., BG-1784 Sofia, Bulgaria.
The Review of Scientific Instruments
|March 2, 2021
Summary
This study presents a tunable high-Q resonator using the General Impedance Converter (GIC). The research derives formulas for GIC impedance, resonance frequency, and Q-factor, incorporating operational amplifier characteristics for precise control.
Area of Science:
- Electrical Engineering
- Analog Circuit Design
- Resonator Technology
Background:
- High-Q resonators are crucial for various electronic applications.
- General Impedance Converters (GICs) offer versatile circuit functionalities.
- Understanding frequency-dependent behavior in GICs is essential for performance optimization.
Purpose of the Study:
- To develop a tunable high-Q resonator based on the GIC.
- To derive a general formula for the frequency-dependent impedance of GICs.
- To establish explicit formulas for resonance frequency and Q-factor that include operational amplifier parameters.
Main Methods:
- Utilized the schematics of the General Impedance Converter (GIC).
- Analyzed the frequency-dependent open-loop gain of operational amplifiers.
- Derived general and explicit formulas for GIC impedance, resonance frequency, and Q-factor.
- Performed voltage measurements using a lock-in amplifier for validation.
Main Results:
- A tunable high-Q resonator was successfully implemented using the GIC.
- A general formula for the frequency-dependent impedance of GICs was derived.
- Explicit formulas for resonance frequency and Q-factor were obtained, incorporating the operational amplifier's crossover frequency.
- Experimental measurements validated the derived theoretical formulas.
Conclusions:
- The GIC can be effectively configured as a tunable high-Q resonator.
- The derived formulas accurately predict the performance of GIC-based resonators.
- The operational amplifier's characteristics significantly influence the resonator's frequency and Q-factor.
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