Numerical Methods for Scientists and Engineers

Preface 1. Introduction 2. Transfer functions 3. The extra element theorem 4. The N extra element theorem 5. Electronic negative feedback 6. High-frequency and microwave circuits 7. Passive filters 8. PWM switching DC-to-DC converters.

Fast analytical techniques for electrical and electronic circuits: PWM switching dc-to-dc converters

A systematic model-parameter-extraction technique is presented for accurately modeling on-chip spiral inductors in radio frequency integrated circuits (RFICs). The model is a pi-circuit with an additional parallel RC network connecting both vertical branches to account for substrate coupling. The extraction starts with extracting the series inductance and resistance at low frequencies. Then, the oxide capacitance is evaluated in an intermediate frequency range. Afterward, the substrate effects including the substrate resistance and capacitance, as well as coupling, are extracted at higher frequencies. All the lumped circuit element values are analytically determined by the network analysis from the measured network parameters (S- or Y-parameters). The proposed approach thus can provide better circuital interpretations of the inductor behaviors for facilitating the design of RFIC inductors. Square and circular CMOS spiral and octagonal BiCMOS7 spiral inductors are investigated to test this technique. Highly accurate frequency responses by the extracted parameters are obtained over a wide frequency band without any optimization. This reveals the validation and capability of the proposed parameter-extraction method.

https://ir.nctu.edu.tw:443/bitstream/11536/8173/1/000260899000050.pdf

Accurate Systematic Model-Parameter Extraction for On-Chip Spiral Inductors

With the ever increasing signal speeds, signal integrity issues of high-speed VLSI designs are presenting increasingly difficult challenges for state-of-the-art modeling and simulation tools. Consequently, characterization and passive macromodeling of high-speed modules such as interconnects, vias, and packages based on tabulated data are becoming important. This paper presents a fast algorithm for passivity verification and enforcement of large order macromodels of scattering parameter based multiport subnetworks. Numerous examples tested on this algorithm demonstrate a significant speed-up compared to the existing algorithms in the literature

Fast Passivity Verification and Enforcement via Reciprocal Systems for Interconnects With Large Order Macromodels

This paper presents an effective modeling methodology for Ultra-wideband (UWB) antennas. The methodology is based on augmenting an existing narrow-band model with a macro-model while simultaneously perturbing component values of the narrow-band model. The narrow-band model is an empirical-based circuit and the macro-model described by rational functions is determined using data fitting approaches. The perturbation of component values of the narrow-band model is achieved by adjustments in SPICE. This method is demonstrated on the example of a 2.5 cm dipole antenna and a circular disc monopole antenna for UWB systems. Simulation results show that this methodology is effective over a wide bandwidth and suitable for modeling most UWB antennas.

/pdf/an-equivalent-circuit-modeling-method-for-ultra-wideband-2w1k787nz8.pdf

An equivalent circuit modeling method for ultra-wideband antennas

This paper presents a new methodology for automated broadband model generation from S-parameter data for interconnects and passive components. The new methodology is based on augmenting an existing equivalent circuit model with a macromodel (black-box) network described by rational functions while simultaneously perturbing the equivalent circuit component values. The macromodel network is determined using standard least-squares or vector-fitting approaches. The perturbation of the equivalent circuit parameter values is achieved during the macromodel generation by means of global optimization based on intelligent search algorithms. The new approach is demonstrated on several two-port test example structures including a broadband probe tip structure and a CMOS spiral inductor.

/pdf/a-new-circuit-augmentation-method-for-modeling-of-sgs0nyr0lh.pdf

A new circuit augmentation method for modeling of interconnects and passive components

A new black-box augmentation methodology for broadband CAD modeling of interconnects and passive elements is presented. The new methodology is based on augmenting an existing equivalent circuit model with a black-box network described with rational polynomial functions while allowing perturbation of the equivalent circuit component values. The approach incorporates the accuracy of black-box modeling while simultaneously preserving the intuition that circuit designers obtain from a 'hand-engineered' equivalent circuit. Exemplary results are shown to illustrate the benefits and accuracy of the method.

https://ieeexplore.ieee.org/iel5/9658/30515/01407603.pdf

A new modeling methodology for passive components based on black-box augmentation combined with equivalent circuit perturbation

This paper presents an alternative derivation of delay extraction for lossy transmission lines based on the method of characteristics and a network formulation. The resulting model consists of ideal transmission lines, controlled sources, and delayless networks, which are approximated by rational polynomial functions. The approach has been implemented in Hspice and is demonstrated for single and coupled transmission lines.

http://ieeexplore.ieee.org/iel5/10457/33185/01563775.pdf

C. Blevins

Papers

A new circuit augmentation method for modeling of interconnects and passive components

A new modeling methodology for passive components based on black-box augmentation combined with equivalent circuit perturbation

Derivation of a network macromodel model with delay extraction for efficient time-domain simulation of lossy transmission lines