Industry News

Pulsed I-V for Nonlinear Modeling

Current-voltage characterization under suitably performed pulsed bias conditions can more closely approximate the dynamic behavior of transistors and diodes under large signal RF conditions. Some understanding of the basics and a relatively simple inst...
Accurate, nonlinear, active device models are critical to achieving design success for circuits such as power amplifiers, oscillators and mixers, using computer-aided engineering (CAE) software such as Agilent Technologies' Advanced Design System (ADS™), Applied Wave Research's Microwave Office™, Eagleware's Genesys™ or Ansoft's Serenade™. Prior work has made it clear...
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The Importance of Phase Accuracy in Differential VNA Measurements

The impact of phase errors in vector network analyzer measurements has become more significant with the increased use of balanced devices and non-50 Ω reference impedances. These significant phase errors are often traceable to calibration or de-em...
The rapidly increasing use of differential RF and microwave circuits has created many new measurement challenges. In S-parameter measurements, for example, transmission phase accuracy could often be ignored with little impact on specification-critical measurements. This is no longer true in the measurement of differential circuits, since seemingly small phase...
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Developing Sophisticated Models for Capacitors, Inductors and Other Passive Components

It is useful to model the non-ideal characteristics of capacitors, inductors and other passive components by using multi-element "schematics," where each element represents some portion of the device's behavior. Traditional models for these devices suf...
Traditional capacitor and inductor models have consisted of two or three elements (capacitor examples are shown in Figure 1 ). The two-element models provide a simple way to define the device. From a circuit designer's viewpoint, the two-element models may suffice for applications where the component is being used...
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Gold Stud Bumps in Flip-chip Applications

As power requirements and operating frequencies increase, more and more designs will look toward ball bumps as an interconnect solution. While solder has traditionally been the incumbent material for these bumps, its limitations have become manufacturi...
As this article is written, it is estimated that 90 to 98 percent of first-level IC interconnects are made using wire bonding technologies. The remaining connections are primarily bump, or flip-chip connections. This ratio is expected to remain the same for the foreseeable future. In general, it will be...
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AMS Radar Project Takes to the Air

In a contract worth approximately US$3 M, AMS, an equal shares joint venture between Finmeccanica of Italy and BAE Systems of the UK, has signed a contract with the Civil Aviation Authority of China (CAAC) to supply two mono-pulse versions of SIR-S, the AMS Mode-S Secondary Radar, to be...
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RF Coplanar Probe Basics

Explanation of the construction, characteristics and usage of coplanar waveguide probes
Coplanar waveguide probes, also referred to as coplanar probes, are the method of choice for launching RF signals on and off a wafer. This article explains their construction, RF characteristics and proper usage. Before the advent of coplanar probes, finding the RF behavior of a die on a wafer...
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New Literature

Analyzer Data sheet This four-page data sheet provides complete detail on the Personal Spectrum Analyzer™, model 401A. Product photographs, descriptions, performance graphs, specifications and ordering information are also provided. Bantam Instruments, Sunnyvale, CA (408) 736-3030. Circle No. 200 Components Catalog The 192-page catalog features hard-to-find programmable devices, memory, microprocessors,...
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Workshops & Courses

Workshops & Courses RF Power Amps, Classes A-S Topics : Provides a detailed explanation of the various classes of RF power amplifiers, and where each class is used in today's wireless designs. Amplifier classes A through S are defined and clearly explained, including the advantages, disadvantages, applications and circuit...
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News From Washington

News From Washington Rockwell Collins Receives Order for Multi-mode Receiver Rockwell Collins is the first to receive Federal Aviation Administration Technical Standard Order approval for a Multi-mode Receiver (MMR) equipped with Microwave Landing System (MLS) functionality that can be implemented in both commercial and military aircraft. Collins MMR is...
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