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Build an Instrumentation Amplifier with Picoamp-Level Input Bias Current

Build an Instrumentation Amplifier with Picoamp-Level Input Bias Current

Discover how the LT1079 quad op-amp minimizes sensor loading in battery-powered designs. Active cancellation and an onboard bridge network ensure maximum precision for resistive sensors.


Arduino-Compatible RS-485 Linear Hall Sensor Board for Magnetic Field Sensing

Arduino-Compatible RS-485 Linear Hall Sensor Board for Magnetic Field Sensing

This project brief describes how to build and use an Arduino-compatible board that reads a linear Hall-effect sensor and reports the measurement over an RS-485 bus.


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.


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.


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.


A Precision Multi-Sensor Data Acquisition Module

A Precision Multi-Sensor Data Acquisition Module

Build a low-noise, 32-bit delta-sigma ADC board designed around the ADS1262. This 10-channel design features integrated signal conditioning for RTDs, thermocouples, and strain gauges.


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.


A Four-Channel RS-422 Differential Line Receiver Module

A Four-Channel RS-422 Differential Line Receiver Module

This project brief describes how to build and use a four-channel differential line receiver module for balanced RS-422 and RS-485 data links.


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.


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.


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.


The Voice Echo: An Arduino Audio Project

The Voice Echo: An Arduino Audio Project

This project brief explains how to construct a PCB-based audio-processing platform with an ATmega328 microcontroller. A link to Arduino code for creating an audio echo is also provided.


The Kilo Lamp: An Interactive Lamp Controller

The Kilo Lamp: An Interactive Lamp Controller

This project brief provides the instructions for building a weight-sensitive LED lamp with an Arduino Uno and a handful of commercially available parts.


Using the Arduino Uno Q to Build a DDS Sine Wave Generator

Using the Arduino Uno Q to Build a DDS Sine Wave Generator

In this project, we'll construct and test a microcontroller-based system that digitally generates analog signals.


Projects Apr 19, 2026 by Don Wilcher
Constructing a Solar-Powered Snake Robot

Constructing a Solar-Powered Snake Robot

Learn how to create a batteryless crawling robot using basic electronic components and a 3D-printed chassis.


Build Your Own Clock With Analog Dials, Part 3

Build Your Own Clock With Analog Dials, Part 3

To complete this project, we add backlight control and temperature-sensing functionality to the clock we built in the previous installments.


Build Your Own Clock With Analog Dials, Part 2

Build Your Own Clock With Analog Dials, Part 2

We continue our design of a clock that uses analog ammeters to display time and temperature. In this installment, we examine the second of the two circuits that enable the timekeeping function.


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.


Building a Push-Pull Level Shifter to Connect an MCU and a Low-Voltage Display

Building a Push-Pull Level Shifter to Connect an MCU and a Low-Voltage Display

In this project, we'll build and demonstrate a discrete analog solution to the incompatible logic levels of an Arduino Uno and an Elecrow e-paper HMI display.


Projects Nov 23, 2025 by Don Wilcher
Hands-ON With AT Commands: The LoRaWAN Trainer

Hands-ON With AT Commands: The LoRaWAN Trainer

We use a Raspberry Pi and free software to build a test platform for IoT systems.


Projects Mar 02, 2025 by Don Wilcher