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Analyzing the Lag Filter’s Effect on PLL Performance

Analyzing the Lag Filter’s Effect on PLL Performance

In this article, we evaluate the designs of two simple frequency synthesizers to learn how a second-order PLL with a lag filter can provide a faster rise time than a first-order PLL.


Understanding the Limitations of the Second-Order Type-1 PLL With a Lag Filter

Understanding the Limitations of the Second-Order Type-1 PLL With a Lag Filter

In this article, we analyze the steady-state errors and Bode plots for a second-order PLL with a simple, first-order loop filter.


Introduction to Second-Order Type-1 PLLs

Introduction to Second-Order Type-1 PLLs

Learn how adding a lowpass loop filter to a PLL with a single integrator impacts both the frequency-domain and time-domain response.


Analyzing a First-Order PLL in Acquisition Mode With a Nonlinear Model

Analyzing a First-Order PLL in Acquisition Mode With a Nonlinear Model

In this article, we'll use a nonlinear mathematical model to improve our understanding of how a first-order PLL locks to a signal.


Basic Principles and Implementation of the Quadrature FM Demodulator

Basic Principles and Implementation of the Quadrature FM Demodulator

Learn how an analog multiplier or AND gate can function as a quadrature detector for FM demodulation.


FM-to-AM Conversion Using the Foster-Seeley Discriminator

FM-to-AM Conversion Using the Foster-Seeley Discriminator

Learn how the Foster-Seeley discriminator, a classic analog circuit for FM demodulation, achieves its superior linearity.


Understanding Slope Detectors for FM Demodulation

Understanding Slope Detectors for FM Demodulation

In this article, we'll analyze the single-tuned discriminator for FM-to-AM conversion. We'll then discuss the balanced discriminator and how it provides improved linearity across a wider bandwidth.


Introduction to Frequency Discriminators for FM Demodulation

Introduction to Frequency Discriminators for FM Demodulation

In this article, we will examine the basic principles of FM demodulation through the simplest frequency discriminator: a differentiator.


Armstrong’s Method of FM Generation

Armstrong’s Method of FM Generation

This article explores the concept of indirect FM generation and the basic operation of the Armstrong modulator.


Introduction to Single-Sideband Modulation: The Filter Method

Introduction to Single-Sideband Modulation: The Filter Method

Learn about a classic amplitude modulation (AM) technique that’s been used in voice transmission for nearly a century.


Introduction to the Balanced Modulator for AM Signals

Introduction to the Balanced Modulator for AM Signals

Learn how the balanced modulator addresses shortcomings of the square-law modulator when generating DSB-SC and conventional AM signals.


Introduction to the Common-Drain Amplifier: Small-Signal Behavior

Introduction to the Common-Drain Amplifier: Small-Signal Behavior

The common-drain amplifier is a single-stage configuration that uses the gate as its input and the source as its output. Learn about its small-signal characteristics in this article.


Using Clever Techniques to Convert a Passive Audio Filter Into an Active Filter

Using Clever Techniques to Convert a Passive Audio Filter Into an Active Filter

This project covers two fascinating and useful circuit design techniques—the Burton Transform and Dualling—that allow us to transform a passive network into an active network while building an audio noise filter.


Projects Jun 02, 2024 by John Woodgate
Common-Mode Chokes: From Working Principles to Important Performance Parameters

Common-Mode Chokes: From Working Principles to Important Performance Parameters

Learn how these simple filters can help you combat common-mode noise with minimal degradation of the desired signal.


Understanding RF Calibration Using Short, Open, Load, and Through Terminations

Understanding RF Calibration Using Short, Open, Load, and Through Terminations

In this article, we conclude our discussion of VNAs by walking through the steps of a SOLT calibration and examining the potential non-idealities of its reference standards.


Frequency Response of the MOSFET Common-Source Amplifier

Frequency Response of the MOSFET Common-Source Amplifier

In this article, we learn about the frequency response of the MOSFET common-source amplifier by examining its s-domain transfer function.


How to Estimate and Enhance the Dynamic Range of a Vector Network Analyzer

How to Estimate and Enhance the Dynamic Range of a Vector Network Analyzer

This article explains how to estimate the dynamic range a vector network analyzer (VNA) needs for a given measurement, then discusses four techniques for boosting the dynamic range to the required level.


Understanding the Significance of Dynamic Range and Spurious-Free Dynamic Range

Understanding the Significance of Dynamic Range and Spurious-Free Dynamic Range

In this article, we investigate two metrics used to characterize the performance of RF test and measurement systems.


Small-Signal MOSFET Models for Analog IC Design

Small-Signal MOSFET Models for Analog IC Design

The small-signal characteristics of MOSFETs play an important role in analog IC design. In this article, we learn how to model MOS transistors' small-signal behaviors.


Building a Circuit to Measure the Effect of Noise on Audio Signals

Building a Circuit to Measure the Effect of Noise on Audio Signals

This project will cover the design, construction, and testing of an analog filter meeting the ITU-R BS.468-4 specification, which aims to evaluate the disturbing effects of noise on audio broadcast signals.


Projects Dec 10, 2023 by John Woodgate