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From Tracking Filters to Demodulation: Exploring the Applications of PLLs

From Tracking Filters to Demodulation: Exploring the Applications of PLLs

In this article, we'll learn about several key applications of PLLs in communication systems, including tracking filters, frequency and phase modulation, and FM and AM demodulation.


Design and Performance of the Class D Output Stage for Piezo Drivers

Design and Performance of the Class D Output Stage for Piezo Drivers

In this article, we explore the operation of a Class D stage with a capacitive load and how it can be used in piezo amplifier design.


Nuvoton Unveils MCU With Cortex-M33 Core Aimed at Smart Devices

Nuvoton Unveils MCU With Cortex-M33 Core Aimed at Smart Devices

The NuMicro M3331 series runs at up to 180 MHz and integrates hardware security, CAN FD, and LED control interfaces across packages as small as 4 × 4 mm.


News Apr 03, 2026 by Luke James
Diode-Based Phase Detectors: Key Principles and Example Circuits

Diode-Based Phase Detectors: Key Principles and Example Circuits

We examine phase detectors that leverage either the nonlinear characteristics or switching capabilities of diodes to perform multiplication.


Build Your Own Clock With Analog Dials, Part 1

Build Your Own Clock With Analog Dials, Part 1

This project turns old-school analog ammeters into a working clock that can also display the ambient temperature.


Second-Order Type-2 PLLs: Bode Diagrams, Bandwidth, and Overshoot

Second-Order Type-2 PLLs: Bode Diagrams, Bandwidth, and Overshoot

Learn how to select the zero frequency, damping factor, and loop bandwidth for one of the most popular PLL configurations.


Introduction to Second-Order Type-2 PLLs

Introduction to Second-Order Type-2 PLLs

This article explains how Type-2 PLLs with an integrator loop filter outperform Type-1 systems. To do so, we'll examine the PLL behavior for frequency step and frequency ramp inputs.


Understanding the Time-Domain Response of PLLs With Lag-Lead Filters

Understanding the Time-Domain Response of PLLs With Lag-Lead Filters

In this article, we examine how adding a zero to the PLL loop filter affects the transient behavior and steady-state errors.


Exploring the Bode Plots of PLLs With a Lag-Lead Loop Filter

Exploring the Bode Plots of PLLs With a Lag-Lead Loop Filter

In this article, we derive design equations for a second-order PLL with a lag-lead filter by examining its Bode plots.


Introducing the Lag-Lead Filter

Introducing the Lag-Lead Filter

Learn how using a pole-zero loop filter improves PLL performance and design flexibility over the simpler lag filter.


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.


Implementing Molex EMI Filter Plates for Superior Electromagnetic Interference Protection | Tech Guide

Implementing Molex EMI Filter Plates for Superior Electromagnetic Interference Protection | Tech Guide

In this Tech Guide, we dive into Molex EMI Filter Plates—engineered to deliver powerful electromagnetic interference protection across demanding systems. Watch now to get started!