Report about the course of Printed Circuit Technology

Pedro M. Vallejo Muñoz

pedromanuelvallejo@gmail.com

Index

1. Introduction
2. Laboratory
3. Examination and recognition of the elements of a PCB
4. Main project
5. Copper-clad project




1. Introduction

This course belongs to the last year of the Bachelor's Degree in Telecommunications Technology Engineering (Branch of Electronics Systems) of the University of Granada. Here , you can see the contents of the course.

The main goal of this report is describe the knowledge and the skills developed during the course of Printed Circuit Technology teached by Mr.  Andrés Roldán Aranda.

2. Laboratory

In this chapter you can see some videos token in the laboratory soldering some components. We use this solder station to solder and disolder components.

2.1. SMD

SMD or Sorface-mount technology is a technology in which the components are mounted directly on the surface of PCBs. SMDs can be one-quarter to one-tenth the size and weight, and one-half to one-quarter the cost of equivalent through-hole parts.

2.1.1. SMD soldering

In the following video you can see the process to solder a SMD resistor, capacitor or similar components:

2.2. Through-hole

Through-hole technology , also spelled "thru-hole", refers to the mounting scheme used for electronic components that involves the use of leads on the components that are inserted into holes drilled in printed circuit boards (PCB) and soldered to pads on the opposite side either by manual assembly (hand placement) or by the use of automated insertion mount machines.

3. Examination and recognition of the elements of a PCB

This part course expects to improve our skill of recognition of elements of a PCB. The following images show the PCB:

In the picture number 1 we can see a hairpin filter. This filter is a structure that uses parallel-coupled lines. In addition, we can observe the angled bends, this angles are common to stripline designs and represent represent a compromise between a sharp right angle.

If we plot S-Parametres of this filter:

In the following picture we can find a solution for delay signal problems. We enlarge a path to synchronize the signals

Via stitching is a technique used to tie together larger copper areas on different layers, in effect creating a strong vertical connection through the board structure, helping maintain a low impedance and short return loops. In RF designs stitching is used in combination with guard rings to create a via wall, helping create an electromagnetically 'quiet' PCB. Via stitching can also be used to tie areas of copper that might otherwise be isolated from their net, to that net. In the PCB I found a case of via stitching:

Mechanical holes are very important to fix the PCB to the mechanical structure:

 4. Main project

I designed a Dimmer. These are devices used to lower the brightness of a light. By changing the voltage waveform applied to the lamp, it is possible to lower the intensity of the light output. Although variable-voltage devices are used for various purposes, the term dimmer is generally reserved for those intended to control light output from resistive incandescent, halogen, and (more recently) compact fluorescent lights (CFLs) and light-emitting diodes (LEDs). More specialized equipment is needed to dim fluorescent, mercury vapor, solid state and other arc lighting.

4.1. Objectives

This project is the most important part in the course and I think it has teach me a lot. I have learn about mechanical, electronic, system, sales and managment engineering. I think the most relevant objectives are:
-to improve organization skills
-to manage multiple CAD software to make a product
-to improve skills to make decisions and optimize time and costs
-to approach us to the real industry world
-to increase knowledge about the electronic market
-to introduce us to the management of a project

4.2. Flow work

This section show how the project has been developped during the time:
-October: requirements definition and pre-prototype designs.
-November: circuit and PCBv0 design, mechanical designs.
-December: mechanical redesign and PCB placement and routing.
-January: assembly and final product.

4.3. Mechanical design

Altium is a software which uses libraries to organize components and their properties and sources. When you do a project with this software you must create yourself the libraries to make your project portable. The following button allow you to download my libraries made for this project:

The followings images show the final mechanical design:


4.4. Electronics design

Altium is a software which uses libraries to organize components and their properties and sources. When you do a project with this software you must create yourself the libraries to make your project portable. The following button allow you to download my libraries made for this project:

You can see the PCB in the following images:

3D view:



Top layer:



Bottom layer:

4.4.1. Electronic simulation

Electronic simulation is done to check if the design of the circuit works. In the following video you can see how if the potentiometer is regulated the output signal changes her amplitude:

4.5. Libraries (Schematic + 3DComponents + Footprints)

The following buttom allow you to download the libreries used to make this product.

4.6. PCB Design

If you want to open this project in Altium you can download it with the buttom below:

4.7. BOM

ComponentQuantityPrice per unitSubtotalSupplier
MMBT2907AT-7-F500,094,5RS
MMBT2222ALT1G20,10,2RS
1N4148WS-V-GS0820,0530,106RS
Triac TS820-600T20,881,76RS
Diode Zener BZX84C1520,140,28RS
Fuse100,7417,41Sonytel
Potentiometer 220 k / 1 W1---
C1 100nF / 400V2---
C 1 uF / 25 V250,092,25RS
C 10 nF / 25 V250,55813,95RS
R 10 k / 0.125 W (0805)4--Laboratory
R 50 k / 0.25 W (1206)2--Laboratory
R 20 k / 0.125 W (0805)2--Laboratory
R 1 k / 0.25 W (1206)1--Laboratory
R 360 K / 0.25 W (1206)1--Laboratory
  TOTAL30,456

4.8. Providers


RS Components
es.rs-online.com


Molex
www.molex.com


Sonytel
Calle de Manuel de Falla, 3, 18005
Granada

4.9. Conclusions

If you think you are going to finish this bachelor without to know how to implement your projects into a real concept. Do this course, you are going to learn professional softwares which are used all over world.
The teacher will give you the knowledge to design a complete product with a correct protocol to obtain a good final result.

 5. Copper-clad project

4.1. Description

It is a voluntary project. 8 team members built a musical instrument able to play 7 notes.

4.2. Electronic design

The main component is a LM555 which is able to generate the frequency necessary through the capacitors a resistors configuration chosen. In this case 493.88 Hz. The signal form is:

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