Module 5: PCB Fabrication

Module 5: PCB Fabrication

Prepared by:

Cesar MendozaApplied Technology Teacher

http://www.electronics-lab.com/blog/?attachment_id=1039

Module Objectives

Learners who successfully complete this module will be able to:

• Define a PCB.

• State the basic functions of a PCB.

• Describe the PCB fabrication steps.

• Use Tina PCB Design software to produce the artwork and a layout for a

simple circuit diagram.

• Develop the PCB for a simple circuit.

Prepared by: CESAR MENDOZA-Applied Technology Teacher

1 Introduction to PCB PCB stands for Printed Circuit Board. PCBs are used in many applications such as radios, televisions, mobile phones…….etc


Basic functions of a PCBThe basic functions of a printed circuit board are (see Figure 5.2):

1. To provide electrical connection between the points those need to be interconnected;

2. To provide insulation between the tracks and other points that need to be isolated;

3. To provide necessary mechanical support to the components mounted on the board;

4. To reduce size and cost, provide better performance and reliability.


PCB Basic Functions


PCB basic

functions

provide electrical

connectionprovide insolatio

n

mechanical support

smaller size

better performan

e

less cost

reliable


COPPER CLAD PCB without Components

PCB with Components


Resist Cover

Etch Resist

Copper Layer

PVC Base

PCB –Copper Clad

PCB Fabrication Steps


PREPARING THE ARTWORKThe artwork can be prepared manually or by using the softwareTINA software is used to prepare the artwork in PCBThe circuit is prepared in TINA and the artwork printed on a transparent sheet

Stage 2. Exposure


Exposure- the first stage in transferring the artwork pattern onto the PCB

1. The artwork is aligned with the copper clad board2. Places in the Ultraviolet (UV) and exposed for 2

minutes3. The UV light will print and protect the etch resist ink

on the tracts

Stage 3: Developing and Rinsing1. In this stage, the etch resist ink is removed from the

unwanted areas of the PCB leaving the tracts.2. The PCB is immersed in a developing solution and the

unwanted etch resist ink is brushed away.3. The PCB is rinsed to make design more clear.


Stage 4: Etching


The PCB is immersed in the Etching solution (Ferric Chloride) which removes the copper from the non-tract areas of the board

Stage 5: Tinning


Tinning is used to protect the copper tracts from humidity

TINNING

TANK

Stage 6: Drilling


In this stage, drill bits are used to drill 1.0 mm holes the mounting of components.


PCB EquipmentThe PCB Workshop is equipped with the following equipments:

1. Mega PCB Lab Station2. Exposure Unit3. PCB Cutter4. Drill5. Edge Rounder






Thank you for listening





Module 5: PCB Fabrication

Documents

pcb pcb

pcb fabricationprepared

board stage

tracts stage

use tina pcb design

copper tracts

printed circuit board

pcbthe circuit