Ying-Cheng Tseng

Transmission-line based modeling for conformal shielding in advance system-in-package (SiP)

In order to efficiently eliminate the noise generated from high-speed integrated circuits, the conformal shielding technology is gradually utilized in advanced System-in-Package (SiP). In this paper, a prediction method based on the transmission-line theory is proposed for evaluating shielding effectiveness (SE) of conformal shielding on SiP. SE measurement of various coating materials is done and presented. By using 4-μm copper, the measured SE successfully demonstrates about 45 dB at the operating frequency of 1 GHz. The proposed model shows a good agreement compared with measured results from 0.01 GHz to 1 GHz.

On-Chip GIPD Bandpass Filter Using Synthesized Stepped Impedance Resonators

By utilizing synthesized stepped impedance resonators (SIRs) with high/low-impedance synthesized coplanar waveguides, a novel on-chip three-pole bandpass filter is realized on glass integrated passive device process. The synthesized SIR, formed by quasi-lumped series inductors and MIM capacitors, provides an effective way to utilize the chip area efficiently. The footprint of the miniaturized filter, 0.045 ×0.029 λg2, is less than one-third the size of the second smallest one in the literature. The upper stopband, extending from 1.4 f0 to 3.77f0, is also the widest among the reported on-chip SIR filter designs. The |S21| at f0 (4.2 GHz) is -3.2 dB, while the bandwidth is 29%.

Radiation mechanism and solution of cable attached differential signals

A common-mode radiation problem induced by cable-attached structure will be discussed and simulated. We will focus on how a cable-attached structure radiates, and how its victim, a Wi-Fi antenna, is affected. Mechanism of common-mode radiation will be showed, and verified by simulated results. Also, a solution using a common-mode filter (CMF) will be proposed, and it will largely suppressed the common-mode radiation from the cable-attached structure. To be more practical, PRBS signals with 212 bit stream are inserted into the system, and the signals received by the Wi-Fi antenna will show that the voltage spectrums in frequency domain are well-suppressed around 2.4 GHz. It proves the usefulness of the CMF.

Design considerations for radio frequency 3DICs

In this paper, we first compare different configurations of RF 3DICs. Through simulations, we research how different TSV geometries affect the dissipation loss, coupling effect, and group delay of RF signals. We also study electromigration issues of power TSVs. Finally, we demonstrate a TSV spiral inductor with a Q factor of 14.9.

A Novel Absorptive Common-Mode Filter for Cable Radiation Reduction

An absorptive common-mode filter (A-CMF) embedded in a four-layer printed circuit board is proposed. Unlike traditional CMFs, for the A-CMF, common-mode (CM) noise is absorbed through the surface mount resistor, so the transmitted and reflected CM noises can be suppressed simultaneously. The proposed A-CMF is synthesized and implemented based on the corresponding equivalent circuit model. To achieve a high-efficiency CM absorption at the desired frequency, through the analytical design equations, the values of the model elements are calculated and are all realizable. In this paper, at the operating frequency of 2.4 GHz, the 15-dB suppression level and 96% absorption efficiency are measured, while the size of the A-CMF is merely

Prediction of near-field shielding effectiveness for conformal-shielded SiP and measurement with magnetic probe

8.65 \times 2.5

A Quadruplet-Resonator-Based Ferrite-Free Choke for Suppressing Noise Currents on Cable Shielding

mm2. Lastly, we designed two in situ experiments for fully demonstrating the suppression performances of CM-induced radiated noise. The measured results, within the operating frequency band of the A-CMF, show the receiving noise of an antenna nearby can be effectively reduced.

A Resonator-Based Suppressor for Mitigating the Noise Transfer on Metal Plates for Control of Electromagnetic Interference

This paper presents a fast prediction method to evaluate the near-field shielding effectiveness (SE) for conformal-shielded System-in-Packages (SiP). By revising the typical EM method to meet SiP circumstances, the near-field SE can be quickly estimated. A simple conformal-shielded SiP module is designed. To experimentally verify the proposed method, two kinds of metallic shielding materials, copper and nickel, are sputtered on the module with different coating thicknesses. In the near-field, the measured SE reaches up to 52 dB for 4-μm copper coating as well as 54 dB for 15-μm nickel coating. The predicted results are closely agreed with simulations and measurements from 0.01 and 1 GHz.

Compact wideband balanced filter for eliminating radio-frequency interference on differentially-fed antennas

This paper presents a novel technique for suppressing cable noise currents, the quadruplet-resonator-based ferrite-free choke (QR-based FFC), to eliminate the gigahertz (GHz) electromagnetic interference caused by noise currents flowing on the cable shielding. This problem is difficult to handle with conventional ferrite materials since their permeabilities dramatically degrade when the operating frequency goes up to several GHz. In this paper, with the aid of QR surrounding on the cable shielding, the FFC forms bandstop responses against the noise currents. The corresponding equivalent lumped circuit model is proposed and investigated. Furthermore, the synthesis procedure is established using microwave filter theory. The QR-based FFC can achieve a high-level current suppression at the desired frequency band. This technology is experimentally verified: a given design example is demonstrated at the operating center frequency of 2.57 GHz. The frequency range of 3-dB current suppression is measured from 2.47 to 2.75 GHz (FBW = 10.8%), where the highest suppression level is up to 36 dB. The FFC-added cable also demonstrates a good result in the reduction of far-field radiation, where the reduction level of radiation peak gain is measured as 7 dB compared with that of a bare cable.

A SMD-type filter solution for EMI/RFI mitigation on high-speed digital interfaces and its application

This letter introduces a novel resonator-based suppressor to mitigate the noise transfer on the metal plates inside electronic devices. Compared with the traditional method using ferrite-based absorbers, which is inadequate to fully eliminate gigahertz (GHz) noise, the proposed solution can achieve a high-level noise rejection within the desired frequency band in GHz range. The unit cell of the suppressor is composed of multiple quarter-wavelength (λ /4) strip resonators. By simply cascading unit cells in series, a higher-order suppressor can be implemented with wider bandwidth and deeper suppression level. In this letter, a third-order example is demonstrated with the center frequency at 2.48 GHz. Its ability to reduce the amount of noise transfer is experimentally verified, where the maximum suppression level is about 20 dB. Lastly, for a complete demonstration of noise mitigation, the near-field intensity on the test board attached with the noise suppressor is measured.