Magnetic DC-Properties of LTCC-Ferrite Material and Their Temperature Dependence

Fulmek, Paul; Haumer, P.; Atassi, Ibrahim; Schweighofer, Bernhard; Wegleiter, Hannes

doi:10.1109/tmag.2011.2173172

Cited by 7 publications

(4 citation statements)

References 4 publications

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“…This material has been characterized for its magneto-static properties in [32]- [34] and has been shown to have a in the range from 3000 to 4000 G ( GHz). Differences are probably attributed to the preparation method (firing temperature profile and lamination pressure).…”

Section: Siw Phase Shiftermentioning

confidence: 99%

An Integrable SIW Phase Shifter in a Partially Magnetized Ferrite LTCC Package

Nafe

Shamim

2015

IEEE Trans. Microwave Theory Techn.

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There is a growing need for small size integrable phased antenna arrays for emerging satellite communications on-the-move applications. Traditional ferrite-based phase shifters are generally bulky due to the need of electromagnets for biasing, yielding them unsuitable for this kind of application. In this paper, a novel compact light-weight substrate integrated waveguide (SIW) based phase shifter realized in a multi-layer ferrite low-temperature co-fired ceramic package with embedded bias windings is reported. By using embedded windings and operating the material in a partially magnetized state, the required bias magnetic field could be significantly reduced from typically about 1000 Oe to less than 50 Oe. Moreover, the presented phase shifter has two modes of operations corresponding to two different biasing scenarios of the SIW, namely, symmetric and anti-symmetric bias. Under anti-symmetric bias, the phase shifter can achieve high nonreciprocal phase shift, whereas under symmetric bias, the phase shift is reciprocal, but the available phase shift is less than the anti-symmetric case. The fabricated prototype operates in the 11.5-13.5-GHz range and has a peak figure of merit (phase shift per decibel of loss) of 102 dB and a maximum phase shift per unit length of 153 cm, which are more than five times the previously reported figures for this technology. Due to the use of embedded windings, the presented phase shifter offers a huge size reduction from the order of cm to mm , making it particularly useful for mobile phased-array applications.Index Terms-Ferrite phase shifter, low-temperature co-fired ceramic (LTCC), substrate integrated waveguide (SIW).

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Section: Siw Phase Shiftermentioning

confidence: 99%

An Integrable SIW Phase Shifter in a Partially Magnetized Ferrite LTCC Package

Nafe

Shamim

2015

IEEE Trans. Microwave Theory Techn.

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“…Besides this, the LTCC core [38]- [40] has a lower permeability and a higher resistivity which allow to reduce the high-frequency effects while providing lower self-inductances.…”

Section: Properties Of the Bond Wire Microtransformersmentioning

confidence: 99%

Design of Low-Voltage Integrated Step-up Oscillators with Microtransformers for Energy Harvesting Applications

Macrelli

Romani

Paganelli

et al. 2015

IEEE Trans. Circuits Syst. I

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This paper describes the modeling of startup circuits in battery-less micropower energy harvesting systems and investigates the use of bond wire micromagnetics. The analysis focuses on step-up Meissner oscillators based on magnetic core transformers operating with input voltages down to 100 mV, e.g., from thermoelectric generators. As a key point, this paper examines the effect of core losses and leakage inductances on the startup requirements obtained with the classical Barkhausen criterion, and demonstrates the minimum transconductance for oscillations to occur. For validation purposes, a step-up oscillator IC is fabricated in a STMicroelectronics 0.32 technology, and connected to two bond wire microtransformers, respectively, with a 1:38 MnZn ferrite core and with a 1:52 ferromagnetic low-temperature co-fired ceramic (LTCC) core. Coherently with the proposed model, experimental measurements show a minimum startup voltage of 228 mV for the MnZn ferrite core and of 104 mV for the LTCC core.

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“…The 40012 is a cast film of magnetic powder [2] designed to be sintered at high temperature to give a ceramic body and get large grains thus achieving substantial magnetic properties (see Table 1). The fabrication of the LTCC core involves three main steps: lamination, cutting, and firing (see left picture of Fig.…”

Section: Fabrication Of the Ltcc Corementioning

confidence: 99%

“…Besides, ferromagnetic materials are now available as low-temperature co-fired ceramic (LTCC) tapes with high resistivity [2]. An overall size reduction of magnetic devices for step-up converters which use external discretes [3] is a strategic issue, as well as the minimization of power losses.…”

Section: Introductionmentioning

confidence: 99%