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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.


A Four-Channel RS-422 Differential Line Driver Module

A Four-Channel RS-422 Differential Line Driver Module

This project brief describes how to implement a four-channel differential line driver module for reliable long-distance data transmission over balanced twisted-pair lines.


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.


A 7 to 60 V Input Buck Converter: A Wide-Range DC-DC Step-Down Module

A 7 to 60 V Input Buck Converter: A Wide-Range DC-DC Step-Down Module

This project brief describes how to build a wide-range DC-DC buck converter capable of delivering a regulated 5.0 or 3.3 V output from input voltages ranging from 7 to 60 V.


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.


The Isolated Half-Bridge: An IGBT Gate Driver Module with Current Sense

The Isolated Half-Bridge: An IGBT Gate Driver Module with Current Sense

This project brief describes how to assemble an isolated half-bridge IGBT gate driver module built around the NCD57085DR2G. It features onboard current sensing and overcurrent protection.


Transferring SPICE Models From LTspice to QSPICE

Transferring SPICE Models From LTspice to QSPICE

In this article, we'll walk through the process of importing SPICE models into QSPICE and demonstrate the basics of using the QSPICE waveform viewer, including measurement markers.


Transferring LTspice Schematics to QSPICE

Transferring LTspice Schematics to QSPICE

In this article, we'll walk through the process of moving an LTspice circuit into QSPICE and learn some QSPICE schematic techniques.


Upgrading My Retro Handheld Gaming Console with Motion Control and an LCD

Upgrading My Retro Handheld Gaming Console with Motion Control and an LCD

Follow my upgrade of a handheld game controller as I add a new 1.8-inch color LCD for animated graphics and an accelerometer module for motion control input.


Building a Resistor Color Code Calculator and Ohmmeter Using Arduino

Building a Resistor Color Code Calculator and Ohmmeter Using Arduino

For this project, I built a handheld resistor color code calculator and ohmmeter using the ATmega328 microcontroller and a 1.8-inch color LCD display.


Moving Data Through an LTspice Parallel-Load Shift Register

Moving Data Through an LTspice Parallel-Load Shift Register

This article demonstrates the operation of an LTspice shift register and discusses details of its schematic and timing relationships.


Creating a Parallel-Load Shift Register in LTspice

Creating a Parallel-Load Shift Register in LTspice

We explore the design and functionality of a digital shift register intended for use in mixed-signal circuit simulations.


An Introduction to Using Logic Gates in LTspice

An Introduction to Using Logic Gates in LTspice

This article explains how to successfully integrate logic gates into an LTspice simulation.


Using Advanced SPICE models to Characterize an NMOS Transistor

Using Advanced SPICE models to Characterize an NMOS Transistor

SPICE models designed for specific CMOS process nodes can enhance simulations of integrated-circuit transistors. Learn where to find these models and how to use them.


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
Simulating the Switching Power Dissipation of a CMOS Inverter

Simulating the Switching Power Dissipation of a CMOS Inverter

When a CMOS inverter switches logic states, power is consumed due to its charging and discharging currents. Learn how to simulate these currents in LTspice.


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
RF Amplifier Stability Factors and Stabilization Techniques

RF Amplifier Stability Factors and Stabilization Techniques

Learn ways to test an RF amplifier's stability, techniques to stabilize its operation, and how RF design software can help you do both.


Implementing a Current-Mode-Controlled Buck Converter in LTspice

Implementing a Current-Mode-Controlled Buck Converter in LTspice

In this article, we use LTspice to discuss the operation of the voltage error amplifier and PWM generator in a current-mode-controlled (CMC) step-down regulator.


An A-Weighted Analog Filter that Mimics the Response of the Human Ear

An A-Weighted Analog Filter that Mimics the Response of the Human Ear

In this project, we design an A-weighted analog noise filter for audio frequencies. The filter provides a variable frequency gain response that is similar to that of our hearing.


Projects Oct 29, 2023 by John Woodgate