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 ...
3.5 Digit Dot Matrix LED Display
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 ...
Controlling PWM Fan with PIC16F684
In this post I’d like to share a design of PWM Fan controller based on PIC16F684 MCU. For Arduino version click here. Previously I’ve designed similar circuits some of them more complex than this one. I recommend you to look ...
Temperature Controlled Fan
Here is another fan controller design based on PIC microcontroller, this time it's temperature controlled and can be used to monitor Hard Drive temperature and adjust the fan speed accordingly or as a case fan controller. This post following recently ...
Digital Lock
In this post I'm going to show you how to build a simple Digital Lock using PIC microcontroller. Instead of building a new hardware design from scratch we are going to use PIC Development Board as a basis for Digital ...
PCF8573P I2C Real Time Clock
In this post I’m going to show you how to interface an I2C Real Time Clock – RTC with PIC microcontroller. Only a basic hardware configuration and a communication protocol are presented here. I’m planning to extend it to a ...
Simple IR Proximity Sensor
This post is about building a Simple IR Proximity Sensor based on PIC16F877a micro controller. Usually these simple circuits are built using discrete components and include an OP AMP for comparing the photo diode voltage to a preset value. Current ...
Digital Voltmeter VFD Display
This is a new revision of 10 bit Digital Voltmeter. For Arduino based voltmeter click here. Recently I’ve published a few voltmeter designs ranging from a simple LED display voltmeters with 8 bit of resolution to a more complex with 10bit ...
2 Channel PC Fan Controller
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 ...
Blinking LED with PIC16F684
This very simple design shows how to make a blinking LED using PIC16F684 MCU. In my previous post I’ve used PIC16F877/86 however most of basic circuits do not require a lot of I/O pins and PIC16F684 small 14 pin package is more ...