Objectives

Group assignment: - Use the test equipment in your lab to observe the operation of a microcontroller circuit board

Individual assignment: - Use an EDA tool to design a development board that uses parts from the inventory to interact and communicate with an embedded microcontroller extra credit: try another design workflow extra credit: design a case for it

Group Assignment

We explored various electronic instruments and electronic components. We learned about the panel keys and operations of equipments.

group assignment page

6. ELECTRONICS DESIGN

Electronic components

Electronic components are the fundamental building blocks of electronic circuits, designed to control the flow of electricity in a system. They can be active (such as transistors and diodes) or passive (such as resistors and capacitors), each serving a specific function within a circuit. When connected on a printed circuit board (PCB), these components work together to form functional electronic devices.

Active and passive components

Active and passive components are the two main types of electronic components used in circuits. Active components require an external power source to function and can amplify, switch, or generate electrical signals. Common examples include transistors, diodes, and operational amplifiers. In contrast, passive components do not need an external power source and mainly resist, store, or control the flow of electricity without amplification. Examples of passive components include resistors, capacitors, and inductors. Both active and passive components are essential for building and operating electronic circuits.

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Resistor

A resistor is a passive electronic component that limits or regulates the flow of electric current in a circuit. It is commonly used to control voltage levels, divide currents, and protect components from excessive current. Resistors are made from materials like carbon, metal film, or wire-wound ceramics, depending on their application. The resistance value is measured in Ohm (Ω). They come in different types, including fixed, variable (potentiometers), and surface-mount resistors (SMRs) for compact circuits.SMD (Surface Mount Device) resistors are small, flat components designed for direct mounting onto the surface of a PCB, making them ideal for compact, high-density circuits. In contrast, through-hole resistors have leads that pass through holes in the PCB and are soldered on the other side, providing strong mechanical bonds and easier handling.

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Capacitor

A capacitor consists of two or more parallel conductive plates that are electrically separated by an insulating material called the dielectric. These plates do not touch each other, and the dielectric can be made of air, waxed paper, mica, ceramic, plastic, or a liquid gel (as found in electrolytic capacitors). When connected to a voltage source, a capacitor stores electrical charge on its plates, creating an electric field between them. The ability of a capacitor to store charge is measured in farad (F), the SI unit of capacitance, where 1 farad (F) = 1 coulomb per volt (C/V). Since capacitors do not allow direct current (DC) to pass, they are widely used for energy storage, filtering, and signal processing in electronic circuits.

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Inductor

An inductor is a passive electronic component that temporarily stores energy in a magnetic field when an electric current passes through its coil. It consists of two terminals and a coil of insulated wire, which can either loop through the air or wrap around a core material that strengthens the magnetic field. Inductors play a key role in managing fluctuations in electrical current within a circuit. The standard unit of inductance is the henry (H).

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Transistor

A transistor is a semiconductor device that plays a vital role in amplifying or switching electronic signals and electrical power. It is composed of three layers of semiconductor material, where the flow of current or voltage between two layers is controlled by applying an electric current or voltage to the third layer. As a fundamental component in modern electronics, transistors are integral to the operation of devices such as radios, computers, and complex integrated circuits. They are available in different types, including bipolar junction transistors (BJTs), field-effect transistors (FETs), and MOSFETs, each designed for specific applications based on its distinct properties and working principles.

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Diode

A diode is a semiconductor device that primarily allows current to flow in one direction while blocking it in the opposite direction. This property makes diodes essential for converting alternating current (AC) to direct current (DC), protecting circuits, and enabling various electronic functions.Diodes operate in two modes:

Forward Bias: When the anode is at a higher potential than the cathode, the diode conducts electricity.
Reverse Bias: When the cathode is at a higher potential, the diode blocks current, acting as an insulator.

Types of Diodes

Rectifier Diode : Used for converting AC to DC.
Zener Diode : Designed to operate in reverse bias and regulate voltage.
Light Emitting Diode (LED) : Emits light when forward-biased.
Photodiode : Converts light into electrical current.

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Integrated circuits (IC)

Integrated circuits (ICs) are essential components in modern electronics, consisting of resistors, capacitors, inductors, diodes, and transistors fabricated onto a single semiconductor chip, usually made of silicon. These components are interconnected to perform specific functions such as amplification, signal processing, computation, and power management. Since the semiconductor material is delicate, ICs are housed in protective plastic, ceramic, or metal packages with metal pins for easy connection to circuit boards. ICs can be categorized into analog, digital, and mixed-signal types, enabling compact, efficient, and reliable electronic devices.

Switch

A switch is an electrical or electronic device that controls the flow of current in a circuit by connecting or disconnecting it. Switches can be broadly classified into mechanical and electronic (solid-state) switches. Mechanical switches, such as push buttons, toggles, and rotary switches, operate through physical movement and can be categorized based on actuation method, contact configuration, poles and throws, and operating states. Electronic switches, like transistors, MOSFETs, and thyristors, have no moving parts and use semiconductor technology to switch circuits efficiently, making them ideal for applications in automation, motor drives, and HVAC systems.

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KiCad

KiCad is a free, open-source Electronic Design Automation (EDA) software suite used for creating schematics and designing printed circuit boards (PCBs). It provides tools for schematic capture, PCB layout, circuit simulation, and generating manufacturing files such as Gerber files. KiCad also includes features like 3D modeling, bill of materials (BOM) generation, and engineering calculations, making it a powerful tool for electronics design.

I downloaded and installed KiCad. Now open KiCad . File → New Project . Name your project

In place symbol tool select for the microcontroller you want to work with.I searched for ATTINY 412, which wasn't available in the library. So i had to manually added it. I used snap eda.Pins were assigned using datasheet. Symbols and footprint were created in snapeda and downloaded.The zip file is then extracted.

Preference → Manage symbol libraries. From folder add your symbol library to the table.

In the same way , Preference → Manage footprint libraries. From folder add your footprint library to the table.

To add git lab kicad library, copy the SSH key. Create a local folder. Clone it inside the folder.

Design 1

In KiCad we have two editors, schematic editor and pcb editor. Open schematic editor.

Using the place symbol tool (shortcut - A) we can add components. By using draw wires tool (shortcut - A) we can make connections between components.

voltage regulator

ATTINY 412

UART

switch

LED

Power LED

External Voltage

To work with pcb editor first we need to define designrules. Open pcb editor. From file -> board setup -> Design rules

The components are reaaranged. to track route simply use shortcut X or we can find it in the right pannel. select edge cut and draw the shape of our pcb.

From the 3d viewer in the top panel we get the 3d model of our PCB.

Design 2

I used XIAO ESP32 C6 microcontroller. For that a new file is created. The symbol and foot print of the same wasn't available in KiCad. So I manually added the symbol and foot print libraries.

Preference → Manage symbol libraries. From folder add your symbol library to the table.