Among these structures, the measured maximum quality factor q of the suspending inductor and frequency at maximum q are improved from 5. Analysis, design, and optimization of spiral inductors and tra. They eliminate the need for hand forming and staking coil in hybrid circuits. Pdf on the design of rf spiral inductors on silicon. Design and optimization of a 10 nh squarespiral inductor. Design and optimization of a 10 nh squarespiral inductor for. On chip spiral inductors are widely used for rf frequency range. All of inductor is fabricated in the standard silicon process with metal layers. Based on the qfactor equation, the layout dependences are investigated. If there is no dc flux in the core, the design calculations are straightforward. Genemala haobijam, design and analysis of spiral inductors english isbn. Basic design, modeling, and optimization a spiral inductor can be built on a silicon substrate by using the multilevel interconnects that are routinely. Symmetric spiral inductors using a similar algorithm described in section iia, the.
Section 2 discusses the design of threedimensional multi spiral inductor and mathematical models of the inductors. A parameterized cell design for highq, variable width and. But the circular inductor is not widely used because only a few commercial. This is followed by the discussions of advanced structures for the enhancement of. To facilitate the design of such components, signi. As a result, simple and clear guidelines for highq inductor design are suggested. The q or quality factor of an inductor is the ratio of its inductive reactance x l to its series resistance r s. The hfss 3d electromagnetic simulation results are presented. Efficient analytical modeling techniques for rapid integrated. Liou abstractpassive components are indispensable in the design and development of microchips for highfrequency applications. Pdf accurate analytical spiral inductor modeling techniques. Design and fabrication of inductors for induction heat.
Spiral filters are complicated structures, with nonzero thickness lines, underpasses, and more than one spiral metal layer possible. Simple accurate expressions for planar spiral inductances stanford. A closed form expression for the quality factor of the spiral inductor, methodologically, is presented as a function of the inductance l ind, metalline width w, spacing s, inner and. The design concept and modeling approach of the typical squareshaped spiral inductor are first addressed. The massachusetts bay technologies msi series of spiral inductor chips are formed by plating and photo etch techniques on quartz substrates. These devices are designed to meet hybrid microwave circuit requirements through ku band. The inductor or coil behave the same way whether the load is a radiating antenna or an electronic circuit. Ocombining these two groups of raw data, we can extract. Onchip spiral inductortransformer design and modeling for. On the design of rf spiral inductors on silicon electron. Characterization and modeling of planar spiral inductors. Several approaches were examined for modeling the planar spiral inductors. On the design of rf spiral inductors on silicon joachim n.
Design guide for cmos process onchip 3d inductor using. Our simple expressions are accurate enough for design and optimization of inductors or of circuits incorporating inductors. It is very important that the inductor has optimal design, meaning optimal. Another importance part of the spiral inductor is the substrate. Cant find the inductors you need for an antenna, a tuner or amplifier. Bowick, rf circuit design, butterworthheinemann, 1982. The coefficients k1 and k2 are structure dependent parameters and are shown in table 2. Accurate modeling of spiral inductors on silicon using planar. Johns, w3jip airdielectric inductors can be made quite easily at home. Each parameter could be modified by using the command set. Inductors in particular are used frequently in radio frequency rf ics such as lownoise amplifiers and oscillators.
Induction coil design has a major impact on your part quality, process efficiency, and manufacturing costs. Study of spiral inductors 31 where lmw is the inductance modified using wheeler expression and. Silvaco design of optimal spiral inductors in expert. In this work, design of pcb inductors for wpt in bio medical applications is presented. The first approximation is based on a modification of an expression developed by wheeler. The iccap project modeling spiral inductors with and without metal1 shielding can be downloaded together with a detailed pdf explaining the steps demonstrated in. The methodology allows designers to specify a desired inductance, total area, and frequency of oper.
Measurements and characterizations of the fabricated inductor is performed and presented in the paper. Pdf on the design of rf spiral inductors on silicon researchgate. This style inductor can be used where low inductance values and gold wire bond is the interconnection method. Within single shot, it also could be hardened by a machined encircling inductor or a socalled encirclingnonencircling inductor. It is very important that the inductor has optimal design, meaning optimal geometry with the best possible characteristics 1. One of the key components in many rf ics applications is the inductor. Presentation new methodology for spiral inductor design. To obtain a high selfresonance, the conductor width is reduced and capacitance. Onchip spiral inductortransformer design and modeling. In this paper, we study the effect of the technological parameters of on chip inductor, the characteristics of on chip inductor is simulated using the matlab simulation. For accurate modeling of the rflw compone nt incircuit performance, measured s parameter files are available upon request. In this work, panar micromachined spiral inductive structures with relatively high inductance at low hzkhz frequencies are designed and fabricated for.
Accurate analytical spiral inductor modeling techniques for efficient design space exploration article pdf available in ieee electron device letters 2712. A total of 19000 inductors were simulated using the program asitic, spanning the entire design space that is of use for rf circuit designs. The inductors spiral trace presents a substantial amount of series resistance, and the close spacing of spiral turns present measurable amounts of stray capacitance that interact with the inductive characteristics. Spiral inductors are often used in mic, mmic and rfic design, particularly below 18 ghz. Some formulas are available for calculating the spiral inductor for rfic applications. Design inductor having a given inductance l, which carries worstcase current imax without saturating, and which has a given winding resistance r, or, equivalently, exhibits a worstcase copper loss of. An inductor is an inductor, it doesnt change its characteristics depending on enduse, although different designs. Analysis, design, and optimization of spiral inductors and.
Optimization of planar spiral inductor and design of. However, correct modeling of the inductor is far from trivial. The approach developed herein is built around an existing composite model available in. These coils have been modeled and optimized using advanced computer automated design tools to produce data and graphs to help you utilize these devices in your own thinfilm or hybrid designs. A commonly used model for designing planar inductors is illustrated. Duringthe past few years, the designandoptimizationof integrated spiral inductors has attracted much interest in both the ic design and the electronic design automation communities. Accuracy in design ing a spiral inductor is important because it is difficult to modify the inductor once you have built it on the pcb. Atp introduces a new line of printed spiral inductor coils in a wide range of values from 2. Pdf design and modeling of miniature onchip spiral. Abstract the design and optimization of spiral inductors on silicon substrates, the related layout issues in integrated circuits, and the effect of the inductor q on the performance of radiofrequency rf building blocks are discussed. The amidon lseries coil forms can easily be used to make almost any inductor. Design and optimization of printed circuit board inductors. Characterization and modeling of planar spiral inductors and pad stack parasitic effects john capwell abstract this thesis concentrates on rfmicrowave characterization and modeling of planar spiral inductors and pad stack parasitics. A parameterized cell design for highq, variable width and spacing spiral inductors manikandan r r1, venkata narayana rao vanukuru2, anjan chakravorty3, and bharadwaj amrutur1 1ece dept.
When used as a choke, a low q is generally desirable to obtain a broadband characteristic. Niknejad master of philosophy in engineeringelectrical engineering and computer sciences university of california professor robert g. In this work, design of a multi spiral stacked solenoidal inductor for bio. Abstractsilicon integrated circuit spiral inductors and trans formers are analyzed using electromagnetic analysis. The design of an ac inductor is quite similar to that of a transformer. I 1 a planar micromachined spiral inductor 1 for integrated. Because of this, coil design is generally based on experience.
Fudan university, 2001 a dissertation submitted in partial fulfillment of the requirements for the degree of doctor of philosophy in the department of electrical engineering in the college of engineering and computer science. Ltd 3electrical engineering dept, iit madras abstractthe onchip planar spiral inductors having variable. We have assembled this 28page guide to help you get the best performance from your induction heating system. Basic design considerations the inductor is similar to a transformer. Optimization of integrated spiral inductors using sequential. Department of electrical and computer engineering, rice university, houston, texas mobius microsystems inc. This thesis concentrates on rfmicrowave characterization and modeling of planar spiral inductors and pad stack parasitics.
W, smallest ratio 1016 comparing two cores with identical area products, ap, for the same design specification, the core with a. Setting the mode of the analysis into fast would hasten the simulations. Analysis, design, and optimization of spiral inductors. So, the target of this project is to design a 10nh square spiral inductor with high quality factor q. For an encircling inductor scanning or single shot, the current. On the design of rf spiral inductors on silicon terpconnect. Spiral inductors on rfic circuits figure 1 are critical for filtering and tuning purposes. Lee, simple accurate expressions for planar spiral inductances, ieee journal of solidstate circuits, oct. Single layer planar spiral coil inductor calculator.
Design and analysis of spiral inductors springerlink. Some coils are held together by clear epoxy ribs, others use scrap pieces of pc board and epoxy. Traditionally, spiral inductors are made in square shape due to its ease of design and support from drawing tools 7. In general, planar spiral inductors are fabricated in integrated circuits, the spiral inductor being the dominant choice since it is a planar inductor and hence easy to fabricate using two dimensional techniques. The thickness of the inductor has only a very small effect on inductance and will therefore be ignored in this paper. Two coil c core single coil c core lamination kj 0. Section 3 discusses the figure ofmerit based optimization process. Inductors can be rectangular or round, so long as you know how to model them. From the performance point of view, however, the most optimum pattern is a circular spiral because it suffers less resistive and capacitive losses. Design and fabrication of highq spiral inductors using mems. This guide provides almost everything you need to design the.
For the first time, we develop an optimization technique for the design of spiral inductors and lc resonators exploiting both the computational efficiency of a cheap circuit model and the accuracy of a fullwave em analysis, based on geometric programming gp and space mapping sm. Although slugtuned inductors are sometimes considered a bit beyond the hobbyist or ham, that is not actually true. The solution is to find the number of turns and all dimensions of the square spiral inductor. Introduction onchip spiral inductor has been widely used in integrated. The spiral inductor lumped element model can have many capacitor and resistor elements to account for all the parasitics that make it less and less ideal as you move up in frequency. Pdf in this paper, a novel approach for designing spiral inductor is proposed. If the wire coil is wound around a core made of a material that is easily magnetised, such as iron, then the magnetic field around the coil is concentrated within the. Spiral printed circuit board pcb inductors are gaining attractions for wireless power transfer ap plications due to their various advantages over conventional inductors such as lowcost, batch fabrication, durability, manufacturability on flexible substrates, etc. Ansys electromagnetics spiral inductor part 1 geometry youtube. A fundamental approach for design and optimization of a. This is to certify that the thesis entitled optimization of planar spiral inductor and design of multilayer pyramidal inductor for silicon radio frequency integrated circuits submitted by genemala haobijam, a research student in the department of electronics and communication engineering, indian institute of technology, guwahati, for the. Spiral inductors are used extensively in microwave circuit resonant elements and as a choke in power supplies.
Design of high quality factor spiral inductors in rf mcmd. Below, we have collected excerpts from this important resource. Accurate modeling of spiral inductors on silicon using. Rf circuit design aspects of spiral inductors on silicon. Simple accurate expressions for planar spiral inductances, ieee journal of solidstate circuits, oct. Setting it slow uses the em electromagnetic analysis and it would take more time to run and finish the. Spiral in cmos nsheet resistance of metal layer can be used only for calculating the dc resistance of the spiral. The authors proposed an algorithm for accurate design and optimization of spiral inductors using a 3d electromagnetic simulator with minimum number of inductor structure simulations and thereby reducing its long computation time. The apparent power, pt, of an inductor is the va of the inductor. Onchip spiral inductortransformer design and modeling for rf applications by ji chen b. Pdf design and comparative analysis of spiral inductor structure. For each inductance value, the number of turns required is shown for coil diameters of 0. A fundamental approach for design and optimization of a spiral inductor 259 used.
A design methodology is developed to search an in ductor design space e. Inductors depend for their action on the magnetic field that is present around any conductor when it is carrying a current. Spiral inductor design for quality factor sanggug lee and sincheol kim abstract. Current status ofor general inductor design, both real silicon measurement data and 3d simulation data are used in the model extraction. Its an inductor with a metallic inner core that increases the inductance and allows the inductor to act as an ef.
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