Sung-Mao Wu

Modeling Noise Coupling Between Package and PCB Power/Ground Planes With an Efficient 2-D FDTD/Lumped Element Method

An efficient numerical approach based on the 2-D finite-difference time-domain (FDTD) method is proposed to model the power/ground plane noise or simultaneously switching noise (SSN), including the interconnect effect between the package and the print circuit board (PCB). The space between the power and ground planes on the package and PCB are meshed with 2-D cells. The equivalent R-L-C circuits of the via and the solder balls connecting the package and PCB can be incorporated into a 2-D Yee cell based on a novel integral formulation in the time domain. An efficient recursive updating algorithm is proposed to fit the lumped networks into the Yee equations. A test sample of a ball grid array (BGA) package mounted on a PCB was fabricated. The power/ground noise coupling behavior was measured and compared with the simulation. The proposed method significantly reduces the computing time compared with other full-wave numerical approaches.

VERY MINIATURE DUAL-BAND AND DUAL-MODE BANDPASS FILTER DESIGNS ON AN INTEGRATED PASSIVE DEVICE CHIP

This work presents extremely compact dual-mode and dual-band bandpass fllter designs based on dual-resonance composite resonators developed by using integrated passive device (IPD) technology on a glass substrate. A dual-mode bandpass fllter is also devised using a symmetric composite resonator with a perturbation element of grounding inductor to determine the fllter bandwidth. Additionally, a feedback capacitive coupling path on the proposed dual-mode fllter is implemented to produce three transmission-zero frequencies in the stopband. Furthermore, the proposed dual-band bandpass fllter is designed in a high-density wiring transformer conflguration with magnetic and electric mixed coupling. In addition to individually determining the fractional bandwidth of dual passbands, the magnetic and electric mixed coupling provides multiple transmission zeros to enhance the isolation between the two passbands and greatly improve the stopband rejection.

Modeling of lead-frame plastic CSPs for accurate prediction of their low-pass filter effects on RFICs

This paper presents a direct extraction method to construct the electrical models of lead-frame plastic chip scale packages for RF integrated circuits (RFICs) from the measured S-parameters. To evaluate the package effects on the reciprocal passive components, the insertion and return losses for an on-chip 50-/spl Omega/ microstrip line housed in a 32-pin bump chip carrier (BCC) package were analyzed based on the established package model. Excellent agreement with measurement has been found up to 15 GHz. When applied to the nonreciprocal active components, the gain variations for a heterojunction-bipolar-transistor array housed in an 8-pin BCC package have also been successfully predicted up to 22 GHz. Both cases have demonstrated that the package acts as a low-pass filter to cause a sharp cutoff for the RFIC components above a certain frequency.

VERY COMPACT FULL DIFFERENTIAL BANDPASS FILTER WITH TRANSFORMER INTEGRATED USING INTEGRATED PASSIVE DEVICE TECHNOLOGY

In this study, a very compact, second-order, full difierential bandpass fllter is presented. To achieve compact circuit area and system-in-package (SiP) applications, the transformer structure is integrated using integrated passive device (IPD) technology on a glass substrate. The coupled resonator synthesis method is used to achieve the bandpass fllter design and suitably adjust the tapped feed-lines to obtain good impedance match at all ports. The area (1:27mm£1:27mm) of the bandpass fllter is efiectively reduced, and the performance, as measured by insertion loss (2.5dB) and CMRR (> 30dB), is still acceptable with such a compact area. Most importantly, this full difierential bandpass fllter is also suitable for SiP applications, as other studies implemented using glass IPD technology have demonstrated.

Electrical performance improvements on RFICs using bump chip carrier packages as compared to standard thin shrink small outline packages

The electrical models of bump chip carrier (BCC) packages have been established based on the S-parameter measurement. When compared to the standard thin shrink small outline packages (TSSOPs), BCC packages show much smaller parasitics in the equivalent model. In the simulation, the insertion and return losses for a packaged 50-/spl Omega/ microstrip line are calculated against frequency. BCC packages are also less lossy than TSSOPs over a wide frequency range. By setting a random variable with Gaussian distribution varied within a certain range for each equivalent circuit element of the packages, the Monte Carlo analysis has been performed to study the package effects on a GaAs heterojunction bipolar transistor (HBT). Again, BCC packages cause less decrement of HBT unity-gain bandwidth than TSSOPs.

Complete methodology for electrical modeling of RFIC packages

A complete methodology based on broadband S-parameter measurement is proposed to establish the electrical models for radio-frequency integrated circuit (RFIC) packages. The research is focused on calibration of the test-fixture parasitics to obtain the intrinsic S-parameters from which an equivalent coupled lumped model can be extracted for any pair of package leads under test. Then a step-by-step optimization scheme is employed to construct an equivalent circuit for the whole package. A real example on modeling a 16-lead Thin Shrink Small Outline Package (TSSOP) has been demonstrated. The established model can account for various package effects at radio frequencies.

Highly Miniaturized Multiband Bandpass Filter Design Based on a Stacked Spiral Resonator Structure

This paper describes a stacked spiral resonator (SSR) structure for designing very compact multiband bandpass filters. The resonant frequencies of the proposed SSR structure can be determined by designing the spiral geometry and controlling the mutual coupling in a stacked structure. The multiple passband bandwidths can then be determined by the spacing of different layer patterns between two coupled SSRs. An adequately designed geometry of the input/output resonator with a tapped-line feed can achieve matching conditions for all passbands simultaneously. Moreover, multiple transmission zeros created on both sides of each passband provide high stopband roll-off rates.

Electrical performance improvements on RFICs using bump chip carrier packages as compared to standard small outline packages

The electrical models of Bump Chip Carrier (BCC) packages have been established based on the S-parameter measurement. When compared to the standard Thin Shrink Small Outline Packages (TSSOP), BCCs exhibit much smaller parasitics in the equivalent circuits. In the simulation, the insertion and return losses for an arbitrary pair of package leads connected through an on-die 50-ohm line are calculated against frequency. BCCs also show better loss characteristics than TSSOPs over a wide frequency range. By setting a random variable with Gaussian distribution varied within a certain range for each equivalent circuit element of the packages, the Monte Carlo analysis has been performed to study the package effects on a GaAs Heterojunction Bipolar Transistor (HBT). Again, BCCs cause less decrement of HBTs unity-gain bandwidth than TSSOPs.

MINIATURIZATION DESIGN OF FULL DIFFERENTIAL BANDPASS FILTER WITH COUPLED RESONATORS USING EMBEDDED PASSIVE DEVICE TECHNOLOGY

This paper presents two full difierential bandpass fllters with small occupied areas. Both fllters are designed with the same basic structure which consists of two double coupled resonators with magnetic coupling. The resonators are stacked up and have the advantage of high coupling e-ciency, reducing the area. Nevertheless, in the basic structure, the insertion loss in the high stopband is above i10dB and therefore does not meet the requirement for bandpass fllter design. Thus, two solutions are introduced to form the proposed fllters. The flrst one integrates the ground plane, while the second one makes the use of an extra transmission zero. With the help of these solutions, two types of full difierential bandpass fllters are implemented on an FR4 using the embedded passive device technology, with the additional purpose of being designed for SiP applications. The passband of the fllters conforms to the WLAN IEEE 802.11a (5GHz) standard. Most importantly, the occupied areas of the two proposed bandpass fllters are only 6mm£6:7mm and 6:6mm£8:3mm respectively. Compared with previous research, area reductions of up to 98.05% and 97.76% can be achieved.

A Novel Compact 2.4/5.2 GHz Dual Wideband Bandpass Filter with Deep Transmission Zero

In this study, a novel compact 2.4/5.2 GHz dual wideband bandpass filter was designed and fabricated on an Al2O3 ceramic substrate. First, a dual-band filter was designed based on two open-loop rectangular ring (OLRR) resonators, which were cascaded using a coupling connection in order to increase the bandwidths of the dual passbands. Diverging U-shaped dual feed input/output transmission lines were used for strong coupling. A shunt quarterwavelength open stub eliminated unwanted harmonic frequencies and transmitted the desired passbands. To achieve this, four open stubs were directly added onto the two OLRR resonators as bandstop resonators to reject undesired frequencies and improve the out-of-band rejection between the two resonant frequencies. The coupling sections between the two resonators were modified using a groove structure to regulate the coupling of the two modes and eliminate the ripple at the designed 5.2 GHz band. According to simulated and measured results, the proposed filter with optimized parameters exhibited dualwide passbands with bandwidths of 530 MHz (22.84%) and 650 MHz (12.29%) at 2.32 GHz and 5.29 GHz, respectively.