This course is a review of design approaches of linear and nonlinear stability analysis in high frequency circuits
Lesson 1 - The Trouble with K-Factor and the Paradox of Choice
In this video, Matt Ozalas discusses the challenges of designing stable high-frequency amplifiers. He introduces the concept of K-factor, and explains why it is not always a reliable indicator of stability. He then discusses the paradox of choice, which refers to the fact that there are often many different ways to design a stable amplifier, and it can be difficult to choose the best approach.
Lesson 2 - The Basics: Loop Gain, Laplace Transform, Cauchy's Principle, Nyquist Plots
Matt Ozalas provides an overview of the basic concepts of loop gain, Laplace transforms, Cauchy's principle, and the Nyquist stability criterion. He explains how these concepts can be used to analyze the stability of high-frequency amplifiers.
Lesson 3 - Loop Gain Techniques: Osctest, Double Null Injection, Bilateral Model
Learn the effects of gain and coupling on amplifier stability. He explains how gain and coupling can cause the loop gain to become positive at certain frequencies, which can lead to oscillation. He then discusses how to mitigate these effects by using techniques such as negative feedback and compensation.
Lesson 4 - Fundamentals: Return Ratio, Driving Point Impedance
Review the use of simulation tools to analyze amplifier stability. He explains how simulation tools can be used to plot the loop gain and Nyquist plot, which can help to identify potential stability problems. He then discusses how to use simulation tools to design stable amplifiers.
Lesson 5 - Modern Implementations: NDF, True Return Ratio
Examine modern implementations of stability analysis. He introduces the concepts of NDF (Normalized Doppler Factor) and True Return Ratio (TRR), and explains how these metrics can be used to analyze the stability of high-frequency amplifiers.
Lesson 6 - Unifying Simulation Approaches: WS-Probe
Focuses the WS-Probe technique for stability analysis. He explains how the WS-Probe technique can be used to unify the different approaches to stability analysis, and how it can be used to design stable amplifiers.
Lesson 7 - Circuit Examples: Bringing it all together
Discusses the challenges of designing stable amplifiers at mmWave frequencies. He explains why mmWave frequencies can be more challenging to design for, and he discusses some of the techniques that can be used to mitigate the challenges.
Lesson 8 - Designing for Stability in High Frequency Circuits
This application note will help engineers understand how instabilities fundamentally arise in their circuit and illustrate how to troubleshoot and resolve these issues up front in the design process before manufacturing. This not only requires an understanding of classic theory and techniques, but also practical knowledge to apply these efficiently using modern design tools such as a novel new impedance probe called the WS-Probe.
Four Secrets to Mastering Millimeter-Wave Communications Circuit Design
Keysight has seen dramatic changes in mobile network devices and infrastructure design, development, and deployment in the transition from 4G to 5G. One substantial challenge affecting circuit design is frequencies extending into the 70 GHz millimeter-wave (mmWave) band. High millimeter-wave frequencies and the drive towards miniaturization directly impact the design of the circuits and systems.