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A 60 W Class-AB Audio Amplifier: A TDA7296-Based Single-Channel Power Amp

A 60 W Class-AB Audio Amplifier: A TDA7296-Based Single-Channel Power Amp

Learn how to construct a robust DMOS-based board featuring mute and standby controls. It easily drives 4 or 8 Ω loads for your next custom stereo or speaker project.


SNR Analysis of FM Modulation with Arbitrary Message Signals

SNR Analysis of FM Modulation with Arbitrary Message Signals

Deriving a general signal-to-noise expression for frequency modulation with any message signal reveals a core trade-off: more deviation buys better noise performance, but only by using more bandwidth.


A 500 mA Power Op Amp Breakout Board With Precision Current Limiting

A 500 mA Power Op Amp Breakout Board With Precision Current Limiting

Safely drive up to ±500 mA into reactive loads. This compact module employs the LT1970A and offers independent 1% source/sink thresholds and onboard fault diagnostics.


Understanding Noise in FM Systems: The Tone-Modulated Scenario, Part 2

Understanding Noise in FM Systems: The Tone-Modulated Scenario, Part 2

This article explores how combining signal and noise power reveals how the FM system’s output SNR scales with carrier amplitude and modulation index.


A Dual 38W Power Amplifier: A Compact STA540-Based Stereo Audio Board

A Dual 38W Power Amplifier: A Compact STA540-Based Stereo Audio Board

This project brief describes how to build a compact dual-channel power amplifier module that delivers 38 W per channel into 4-ohm speakers using STMicroelectronics' STA540 audio amplifier IC.


Understanding Noise in FM Systems: The Tone-Modulated Scenario, Part 1

Understanding Noise in FM Systems: The Tone-Modulated Scenario, Part 1

Explore how frequency-modulated waves resist interference. We break down the demodulator architecture and derive the exact output signal power for a sinusoidal message.


Understanding the Noise Performance of AM Receivers with Envelope Detection

Understanding the Noise Performance of AM Receivers with Envelope Detection

Envelope detection is simple, but that simplicity has a noise-performance cost. Here’s how much SNR conventional AM gives up compared to its coherent counterparts.


An Ultra-Low-Noise Pre-Amp For Audio Applications

An Ultra-Low-Noise Pre-Amp For Audio Applications

Build an ultra-low-noise preamplifier with a JFE150 JFET and OPA202 op-amp, perfect for high-impedance sensors, hydrophones, guitar pickups, microphones, and turntables.


Analyzing the Noise Performance of Coherent SSB Demodulators

Analyzing the Noise Performance of Coherent SSB Demodulators

Using a graphical approach, we show that coherent SSB demodulation leaves the input and output SNR unchanged, then compare its noise performance to DSB-SC and baseband systems.


Understanding SNR in DSB‑SC Coherent Detection: A Graphical Approach

Understanding SNR in DSB‑SC Coherent Detection: A Graphical Approach

Visualizing how correlated and uncorrelated signals combine offers an intuitive look at power transformation. See how this difference boosts baseband power to double the output SNR.


Designing a Tuneable Ultrasonic Filter

Designing a Tuneable Ultrasonic Filter

Learn how to build a constant-bandwidth band-pass filter covering 20 kHz to 60 kHz, with an integrated frequency counter for precise tuning.


Evaluating the Noise Performance of Coherent DSB‑SC Demodulators

Evaluating the Noise Performance of Coherent DSB‑SC Demodulators

In this article, we'll learn how to calculate the noise power and signal-to-noise ratio (SNR) of a double-sideband suppressed-carrier communication system.


Class AB vs. Class D: Understanding the Trade-Offs for Piezo Driver Design

Class AB vs. Class D: Understanding the Trade-Offs for Piezo Driver Design

In this article, we explore when to choose a Class AB or Class D output stage for your piezo amplifier design. We'll also examine the Class D stage's power supply requirements.


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.


Evaluating the Class AB Output Stage for Piezo Driver Design

Evaluating the Class AB Output Stage for Piezo Driver Design

We examine the basic requirements of piezoelectric amplifiers and how Class AB operation can meet them.


Using Gilbert Multipliers as Phase Detectors in PLLs

Using Gilbert Multipliers as Phase Detectors in PLLs

This article explores the operation of the Gilbert-cell phase detector for both small and large signals.


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.


Introduction to the Gilbert Multiplier

Introduction to the Gilbert Multiplier

This article explores the Gilbert cell, a widely used analog multiplier circuit.


Dynamic Nonlinearity in RF Power Amplifiers: Insights From Two-Tone Testing

Dynamic Nonlinearity in RF Power Amplifiers: Insights From Two-Tone Testing

This article explores the effect of signal bandwidth on the linearity of power amplifiers, including the impacts of cascaded RF gain stages.


Practical Insights Into Narrowband FM With a Single-Frequency Input

Practical Insights Into Narrowband FM With a Single-Frequency Input

In this article, we’ll use phasor diagrams to compare narrowband FM and conventional AM. We’ll also discuss the problem of oscillator phase noise and work through an example problem.