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This article introduces an innovative four-port dual-path inductor designed to deliver two distinct inductance values to the resonator of a voltage-controlled oscillator (VCO). The switching between the inductor’s two excitation modes, even and odd, is determined by the differential excitation’s input polarity, eliminating the need for a series switch. Thus, the inductor has a high-quality factor ( Q ) in both modes. The inductances in these modes can be independently set based on desired frequencies. This inductance change achieves coarse frequency tuning, while fine-tuning is realized by a conventional 2-bit capacitor bank with a small-size varactor. This inductor is well suited for designing multiband VCOs aimed at widely spaced operation frequency bands. Apart from the inductance change, a particular case of mode-switching capacitor is employed to extend to another frequency band in between the low and middle bands, achieving triple-band oscillation. As a result, this article presents two VCOs designed using the proposed inductor: one in class-D biasing in a 65-nm CMOS process and another with class-B biasing in a 180-nm BiCMOS process. Both VCOs successfully oscillate across three distinct frequency bands, centered at 19, 28, and 36 GHz, while maintaining outstanding phase noise and minimal power consumption. Measurement results show good match with simulation, resulting in a peak figure of merit (FoM) of 185.7 dBc/Hz at 18.5 GHz, and occupy 0.088- mm2 (250 × 350 μ m) area in both processes.
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Effective High-Speed via Model Considering Equivalent High-Order-Mode Inductance
A high-speed via model considering equivalent high-order-mode inductance for frequencies above 70 GHz is proposed in this article. The proposed via model, which considers the equivalent high-order-mode inductance, is a high-accuracy and high-bandwidth via model, improved from the previously proposed mode-decomposition-based equivalent via (MEV) model. The equivalent high-order-mode inductance is an inductance produced by the magnetic fields of high-order modes in the via domain. By including the empirical equivalent high-order-mode inductance, the proposed via model accurately predicts the insertion and return losses of the via with a large antipad size up to the frequency of 150 GHz, which expands the application range of the previously proposed MEV model. In this article, the limitation of the previously proposed MEV model is analyzed by comparing the input impedance extracted from the MEV model and the full-wave simulation. An empirical closed-form formula is proposed to calculate the equivalent high-order-mode inductance at high frequencies to improve the accuracy of the previously proposed model. In addition, the proposed single high-speed via model was expanded to a differential via pair model. The proposed high-speed via model was verified using simulation and measurement results.
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- Award ID(s):
- 1916535
- PAR ID:
- 10695008
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Signal and Power Integrity
- Volume:
- 3
- ISSN:
- 2768-1866
- Page Range / eLocation ID:
- 169 to 177
- Subject(s) / Keyword(s):
- Integrated circuit modeling Inductance Analytical models Impedance Mathematical models Predictive models Frequency measurement Dielectrics Capacitance Accuracy High-speed electronics Magnetic Field Chemical Components Insertion Loss Higher-order Modes Return Loss Full-wave Simulation Dielectric Constant Numerical Examples Restricted Model Electromagnetic Field Bottom Layer Equivalent Circuit Coaxial Printed Circuit Board Relative Permeability Circuit Model Parallel Plate Frequency Bandwidth Equivalent Circuit Model Radius Ratio High Frequency Structure Simulator Domain Decomposition Simulated Impedance Test Board Mode Decomposition Method Energy Perspective Equivalent high-order-mode inductance high-speed via measurement mode-decomposition-based equivalent via (MEV) model
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1109/TSIPI.2024.3487539
