Author - Ligo George

SPI Communication

SPI – Serial Peripheral Interface

SPI (Serial Peripheral Interface) is a full duplex synchronous serial communication interface used for short distance communications. It is usually used for communication between different modules in a same device or PCB. SPI devices communicates each other using a master slave architecture with a single master. Multiple slaves are supported through individual slave select lines. SPI Interface SPI is called as a 4-wire bus as it requires four wires for its communication as shown below. In the case of single slave [...]

Intel Core i7 Processor

What is a Microprocessor ?

What is a Microprocessor ? A microprocessor is an integrated circuit (IC) which incorporates core functions of a computer’s central processing unit (CPU). It is a programmable multipurpose silicon chip, clock driven, register based, accepts binary data as input and provides output after processing it as per the instructions stored in the memory. Block Diagram of a ComputerBlock Diagram of a ComputerHow does a Microprocessor work ? A processor is the brain of a computer which basically consists of Arithmetical and Logical [...]

EasyEDA vs DipTrace vs OrCAD

EasyEDA vs DipTrace vs OrCad

Today I am gonna write about my PCB designing journy that happend before 8 year. I started doing hobby circuits before 8 years and now I am doing professional circuits. Phase 1 : Hand Drawn (no Softwares) I started desiging PCB manually without using any softwares. Mostly I used graph papers to design PCB as it was very easy to make measurements and alignments. Several itrations of drawing was required to make even a small circuit. After the design is completed, I [...]

Virtual Ground - Opamp

Virtual Ground – Opamp

What is Virtual Ground ? As the name indicates it is virtual, not real ground. For some purposes we can consider it as equivalent to ground. In opamps the term virtual ground means that the voltage at that particular node is almost equal to ground voltage (0V). It is not physically connected to ground. This concept is very useful in analysis of opamp circuits and it will make a lot of calculations very simple. Virtual Ground – Opamp Lets see how the [...]

ESP8266 - WiFi SoC

ESP8266 – WiFi SoC

WiFi SoC (System on Chip) ESP8266 is the most popular and low cost WiFi SoC with TCP/IP stack and a low power 32 bit microcontroller manufactured by Espressif, a Shanghai based Chinese manufacturer. As you might already know, nowadays IoT (Internet of Things) is an emerging field. This is the one of the most popular and low cost solution for connecting ‘Things’ to internet via WiFi. ESP8266 – WiFi SoC   ESP8266 belongs to Espressif System’s Smart Connectivity Platform (ESCP) which is a set of [...]

LED Chaser using 4017 and 555 Timer - PCB

LED Chaser using 4017 Counter and 555 Timer

Introduction A simple LED chaser hobby circuit can be made using 555 timer and CD4017 counter IC. You can use this circuit for decorative purposes. By modifying the circuit in a proper way, you can even use this to control lights working on AC mains. Components RequiredCD4017 Counter IC – 1 555 Timer IC – 1 LED – 11 680Ω Resistor – 11 10KΩ Resistor – 1 10KΩ Variable Resistor – 1 10μF Capacitor – 1 0.01μF Capacitor – 1 9V Battery / Power Supply – 1Circuit Diagram LED Chaser using [...]

Rain Alarm using 555 Timer - PCB

Rain Alarm using 555 Timer

Here is a simple and interesting hobby circuit that can be made using the popular 555 timer IC. As you might already know, a 555 Timer can be easily wired as Astable, Monostable or Bistable multivibrator. This circuit can be used as rain sensor, water overflow sensor or as a water level sensor. This circuit make use the principle that normal water can conduct some amount of electricity (PURE water is not a good conductor of electricity but water seen [...]

LCD Glass Panel - Liquid Crystal Display

LCD Display – Fundamentals

LCD Glass Panel – Liquid Crystal Display LCD or Liquid Crystal Display is a flat electronic display which is very commonly used in digital watches, calculators, laptops, televisions etc. It make use of light modulating properties of  liquid crystal and polarization of light for its operation. Low power consumption, less thickness and less weight of LCD enables its use in battery powered and portable applications. Prerequisites Light is an electromagnetic radiation which stimulates sight and make things visible. It is produced by vibration [...]