This post is about building a simple LED controller circuit. Several articles were published on this subject. Here is just one link to similar design that can be useful. Search the site for more information. Current design  relies on well-known technique to ...

This implementation of Arduino based PWM Fan Controller is simple circuit that allows controlling fan speed by varying the duty cycle of the output signal. For PIC16F684 version click here. I’ve tested with Deepcool 120mm fan and it works OK, ...

This post is about building a simple PIC16F88 based DC motor controller. Motor speed and direction can be controlled by two push buttons SW1, SW2. One for motor speed and the other for polarity. This post follows recently published projects like PWM ...

MAX7219 is a serial input/output common-cathode display driver. It can interface the microcontroller to 7-segment numeric LED displays, bar-graph displays, dot matrix display or  individual LEDs. This IC has some very useful features like built in decoder, multiplex scan circuitry, ...

Solar power mobile charger can be built by tweaking digital power supply schematic. The Software/Hardware stayed almost the same as the original circuit.Current design has the same overcurrent protection and output voltage can be changed by pressing SW1. Voltage and Current ...

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 ...

Up Down Counter design based on Arduino MEGA compatible board is the topic of this article.it uses 2x16 LCD display to show the counter values and 4x3 keypad to input initial 3 digit number.The counter will count Up/Down according to ...

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 ...

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 ...

In this post I'll show you how two QDSP-L149 5x7 dot matrix  LED Displays can be used to create a  4 Digit display module. The trick is to change  the roles of rows and columns. So now each 5x7 Dot ...