Chi-Hsuan Cheng

A novel TSV model considering nonlinear MOS effect for transient analysis

A novel equivalent circuit model of through-silicon via (TSV) considering the time-dependent capacitance due to metal-oxide-semiconductor (MOS) effect has been proposed. This model can characterize the variance of capacitance between metal and silicon substrate caused by the differential change of depletion region width as the voltage applied on the TSV changes with time. Compared to conventional TSV models, the capacitance has a 70% difference when the TSVs applied voltage transits from low state to high state. Besides, 3% difference of eye height and 100% difference of eye jitter can be observed in eye diagram by SPICE simulation.

A New Broadband Common-Mode Noise Absorption Circuit for High-Speed Differential Digital Systems

A novel concept of the absorptive common-mode filter (A-CMF) is proposed for solving electromagnetic interference and RF interference problems in high-speed differential digital systems. The A-CMF is realized by a balanced four-port circuit with both horizontal and vertical symmetry. The common-mode (CM) noise can be terminated (or absorbed) by the resistors in the A-CMF and is thus transferred to heat. In addition, the signal integrity of differential signals can be well preserved by the A-CMF. Theory and design procedures are developed to determine corresponding element values of the A-CMF. A design sample is realized by an integrated passive device process on glass substrate. The circuit size is only 1 mm2. Results of measurement and full-wave simulation have good consistency. It will be found that the CM power loss (or absorption) ratio is over 80% from 4 to 14 GHz in measurement, and the differential-mode cutoff frequency can maintain up to 9 GHz with insertion loss, which is good enough for high-speed digital system applications. Finally, the eye diagram at the A-CMF output does not degrade significantly even when the differential data rate is up to 5 Gb/s.

An Equation-Based Circuit Model and Its Generation Tool for 3-D IC Power Delivery Networks With an Emphasis on Coupling Effect

In this paper, a methodology to characterize the electrical behaviors of power delivery networks (PDNs) in 3-D integrated circuits is presented. An automation tool is developed to effectively construct SPICE compatible equivalent circuit models of target PDNs. The core of the tool consists of three equation-based algorithms, which not only model the planar PDN and through-silicon vias in detail, but also the interactions between them through the silicon surface. Simulation results from the proposed SPICE model are in close agreement with the ones obtained from the full-wave simulator up to 40 GHz with more than 100 times speedup.

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

A compact dual-band common-mode filtering component for EMC in wireless communication

8.65 \times 2.5

A novel common-mode filter for multiple differential pairs with low crosstalk and low mode conversion level

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.

An Accurate and Fast Substrate Noise Prediction Method With Octagonal TSV Model for 3-D ICs

A dual-band common-mode filter is proposed to improve the electromagnetic compatibility (EMC) of wireless communication. Implemented in low-temperature co-fired ceramic (LTCC) fabrication as a component, the filter is with a compact size of 3 × 3 mm2. The common mode noise can be reduced over 10 dB form 1.3 GHz to 3.2 GHz and from 5.0 GHz to 6.0 GHz, where the most-used wireless communication bands are involved. Besides, insertion loss of differential mode signal is less than 3 dB from DC to 8 GHz, which implies high data transmission quality.

A radiation prediction method based on partial element equivalent circuit

In this paper, a two-pair common-mode filter is proposed to solve the crosstalk and mode conversion problem of conventional ones in multi-pair form, such as USB3.0 and PCIExpress II. Coupling of the two differential pairs is obviously reduced by a shielding ground plane between them. Moreover, mode conversion problem resulted from asymmetry is also solved. Some simulations have been done to prove the good signal integrity over gigahertz bands brought by the proposed structure, including low loss and distortion of differential mode, a deep transmission zero to suppress common-mode noise, and lower crosstalk and mode conversion level.

A prediction method of heat generation in the silicon substrate for 3-D ICs

In this paper, a refined equivalent circuit model considering semiconductor effect of 3-D ICs is proposed based on three-dimensional transmission line matrix method. In the proposed model, the depletion region around a through silicon via (TSV) is modeled as distributed voltage-dependent capacitors and resistors. With the proposed model, noise behaviors could be accurately obtained under relatively short simulation time when compared to the time needed by full wave simulators. The simulation result of the proposed model is aligned with both ANSYS HFSS and TCAD Sentaurus in frequency and time domains while the simulation time is greatly reduced to less than 1%. The influence of TSV-induced substrate noise on an active circuit is demonstrated using the proposed model. The CMOS inverter affected by the noisy substrate shows up to 34-mV deviation at the inverter output when compared to the inverter on a noise-free substrate.