Updated: Nov 3
As we know Designing and tweaking electronic circuits is done on development boards like breadboard or dotted PCB.
Arduino Uno Development Board
Arduino Uno is a microcontroller development board based on the Atmel ATmega328 MCU. The Arduino Uno has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button. This Arduino MCU board contains everything needed to support the microcontroller. Simply connect it to a computer with a USB cable or power it with an AC-to-DC adapter or battery to get started. The Arduino Uno MCU board can be powered via a USB connection or with an external power supply. The power source is selected automatically.
Stating with Schematic design
In schematic designing, we do subcircuit designing so that our schematic fits in less space. The subcircuits are the DC power supply, Voltage regulator, Analog and digital pins, Reset and LED circuit, ATMEGA328P, and FTDI connector.
DC Power supply unit: In this sub-circuit, we will connect the DC jack, 2P connector, capacitor, resistor, and LED together.
Voltage Regulator: In the case of the voltage regulator we are connecting 7805 IC which is used to convert high input voltage to low input voltage of 5V.
Reset and LED circuit: In this sub-circuit, we will be connecting a push button to the reset pin of the ATMEGA328P. This is used to reset our microcontroller, and whenever the reset button is pressed our LED will blink.
Analog and Digital pins: As we already know Arduino Uno has 14 digital pins(D0-D13) and 6 analog pins(A0-A5). So we use headers to connect these pins to the respective Arduino pins.
These are the sub-circuits, we can connect them each by making use of Net Labels present in the EasyEDA tool.
Schematic view of Arduino Development Board ATMEGA328P.