LED Aquarium Lighting Featured Image

LED Aquarium Lighting

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 ...
9 Volt Battery Charger Featured Image

9 Volt Battery Charger

9 Volt batteries extensively used in various electronics measurement equipment. Powering these devices with  rechargeable batteries can be a cost effective solution. In this post a simple Lithium-ion 9 Volt Battery Charger design with overcharging protection will be presented. Charger is ...
LCD-Countdown-Timer-Arduino-Featured-Image

LCD Countdown Timer Arduino

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 ...
LCD Digital Dual Voltmeter Amperemeter Featured Image

Dual Voltmeter Amperemeter LCD

In this post a simple Digital Dual Voltmeter and Ampere meter design will be shown. It uses PIC16F876A microcontroller and 2x16 LCD display and has 2 input channels for measuring voltage in 0-25v range and current up to 500mA. The ...
LCD Alarm Clock Featured Image

LCD Alarm Clock

Due to popular demand I've modified digital clock design to work with LCD display instead of 7-Segment LED as described in this post. For Arduino version click here. All the capabilities of LED version have been maintained in current project. 1 ...
Simple Digital Voltmeter Featured Image

Simple Digital Voltmeter

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 ...

Basic LCD Frequency Counter with Raspberry Pi

Basic Frequency Counter with Raspberry Pi can be built in less than 15 minutes and does not require any additional components. The input signal is a square wave with 3v amplitude connected to one of Raspberry I/O pins.Design schematic is ...
Digital Alarm Clock Featured Image

Digital Alarm Clock

Digital Alarm Clock design based on PIC16F876A will be demonstrated in this post. Various modules from earlier project were implemented in  current design hardware and source code. For example it uses the same 7-Segment Display and multiplexing routing as in ...
Arduino-with-DS3231-Real-Time-Clock-Featured-Image

Arduino with DS3231 Real Time Clock

In this post I’ll show you how to interface a RTC module DS3231 Real Time Clock  with Arduino. This particular module uses I2C protocol to transfer current time to a micro controller. DS3231 library and header files should be installed ...
Arduino-PWM-Fan-Controller-Featured-Image

Arduino PWM Fan Controller

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, ...