A simple bargraph voltmeter can be built using 2x16 LCD or compatible VFD display. For Arduino version click here. This design utilizes PIC16F877 microcontroller and its ADC block to convert 0 – 5V input voltage to a binary number shown ...

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 ...

Relay controlled by light intensity can be implemented using Arduino UNO compatible board. In this case Keyestudio UNO R3 and AD/DA module with PCF8591 chip. Similar simpler design is available here. On this particular module a photoresistor and a potentiometer ...

In this post I'll show a more general approach for circuits prototyping. Instead of building each individual design to validate its operation why not to design a basic PIC16F877A based Development Board. Current design have all the necessary features of ...

In this post I'll show how you can drive 7 Segment LED display with PIC16F876A. Instead of using a dedicated IC’s like 4511 we’ll program the micro controller to convert  BCD input code 0 – 9 to a 7 Segment LED ...

Digitally Controlled Power Supply from 0-14 Volt based on PIC16F876A will be demonstrated in this post. This is a modification of Digital Power Supply 2.5-12V article and has similar characteristics. The most noticeable difference is the use of PCF8591P I2C Digital to ...

In this post a 1 axis basic digital level design will be presented. This circuit is based on Arduino UNO board and MPU6050 accelerometer and gyroscope chip. The communication is done using I2C interface. MPU6050 module address can vary depending ...

In this post I’ll show you how to build a RFID reader for security access based on Arduino MEGA board. The code I've used is a modified version of a design that was published at Arduino project hub. I added ...

8x8 LED Matrix chaser based on Arduino MEGA compatible board will be presented in this post. It uses a LED dot matrix display module with two 74HC595 shift register chips connected in serial to control the LED output. Similar design ...

In this post I’ll show how to build a basic kinetic watch winder using PIC microcontroller and stepper motor. Kinetic watches do not require changing the battery as frequently as in quartz watch however despite their many advantages they have ...