Following recently published article about building a PWM Fan Controller here is another simple controller design. This time it’s a 2 Channel PC Fan Controller for standard 12V Fans. It uses software implementation of PWM but instead of directly driving PWM ...

Interfacing LCD Display with serial Interface like I2C can save microcontroller I/O making it a practical alternative to a standard parallel 8 bit interface. We’ll use PCF8574 I2C port expander and PIC16F876A microcontroller to establish IIC communication by 2 lines, ...

Raspberry Pi based Digital Clock with 16×2 LCD display is a relatively simple project.It requires only a small set of components and can be completed in less than an hour. Previously I’ve published similar designs based on other popular platforms ...

Here is another modification of a digital voltmeter. This time with 7 – Segment LED Display. These circuits seems to be more popular than other designs so I’ve decided to  publish another variant. You can find 4 variations of digital voltmeter on ...

Simple digital voltmeter can be built by using PIC microcontroller and a few discrete components. PIC16F877A 10 bit ADC module was used for this purpose, we’ll work only with 8 upper bits to translate input voltage to digital form and ...

Generating Sine wave is a relatively simple task. It can be done by adding MCP4725 12bit DAC to Raspberry Pi. For Arduino version based on PCF8591 IC click this link. This setup is based on I2C interface and works by ...

This post is about building a 3-digit countdown timer based on Arduino MEGA. Up/Down counter also available at this link. The timer will wait for 3-digit number to be entered via 4x3 keypad and then start counting down to zero ...

LM35 is a temperature sensor that outputs a voltage proportional to the surrounding temperature in centigrade. In this post I’ll show how this device can be connected to Arduino MEGA board to build a thermometer that shows the current temperature ...

Recently I was asked to build an aquarium lighting controller prototype to provide variable brightness during its operation and ability to program  ON/OFF times. 25 blue and white diffused 10mm LED were used to illuminate the aquarium. The main requirement from ...

Basic frequency counter capable of measuring 0-5V square wave up to 100kHz can be built using just 2 components: Arduino MEGA board and 2x16 LCD display. For PIC16F876 version click here. Frequency counter code is also very simple. It uses ...