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INTRODUCTION

A PRINTED CIRCUIT BOARD or PCB is used to mechanically support and

electrically connect electronics components using conductive pathways, or traces, etched

from copper sheets laminated onto a non-conductive substrate. I t is also referred to as printed

wiring board (PWB) or etched wiring board. A PCB populated with electronics components

is a printed circuit assembly (PCA), also known as a printed circuit board assembly (PCBA).

PCB’s are rugged, inexpensive, and can be highly reliable. They required much more

layout effort and higher initial costs than either wire-wrapped or point-to-point constructed

circuits, but are much more cheaper and faster for high volume production. Much of the

electronics industry PCB design , assembly , and quality control needs are set by standard

that are set by standards that are published by the IPC organizations .

Single or double sided boards consist of a core dielectric material, such as FR-4 epoxy

fiberglass, with copper plating on one or both sides. This copper plating is etched away to

form the actual copper pads and connections traces on the boards surfaces as part of the board

manufacturing process. A multilayer board consists of a number of layer dielectrics materials

that has been impregnated with adhesives and these layers are used to separate the layer of

copper plating.

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PCB DataPreparation

Laminatepreparation

Drilling &

Cleaning

Outer layerimage

transfer

Surface

Finish

FinalFabrication

Testing &Inspection

a) Draw and explain flow for the manufacture of single layer and multilayer rigid

Printed Circuit Boards.

SINGLE LAYER FLOW DIAGRAM

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EXPLAIN FOR THE PROCESS FLOW SINGLE LAYER

PCB DATA PREPARATION

Files transfer from PCB design house to PCB manufacturing

#Gerber files, drill files, fabrication drawing, customer specification

File review by PCB manufacturer

Creation of PCB tooling

#Photo-tool for image transfer – image created by PCB software is

reproduced on film using laser photo plotters

Drill files

Profile routing files

All tooling is stepped and repeated for optimum utilization of standard panel

(24”x18”)

PHOTO PLOTTER ARTWORK

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LAMINATE PREPARATION

Dielectric material : woven glass fiber or paper

Material depends on the function of the PCB. Some perform better some

environment than other (heat, humidity), more suitable for particular

manufacturing process (hole punching). Most widely use is FR4/CEM

Copper foil is rolled or electrolytic ally deposited on the base laminate

Core laminate is sheared to panel size

Core material is cleaned mechanically and/or chemically

Removal of surface contamination required to promote subsequent adhesion

of photo resist

Some PCBs have trace layers inside the PCB and are called multi-layer PCBs. These

are formed by bonding together separately etched thin boards.

Core are pinned in a stack with sheet of prepare separating the copper

layer. Outer layer are made with a foil of copper.

Stack is pinned between heavy metal plates creating a “book”

“Book” is put it a heated hydraulic press for about 2h

Prepare is available in different styles with varying amounts of resin

and glass fibers. This allow the manufacturer to control thickness

between layers and thickness of the overall PCB

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LAMINATION

Core are pinned in a stack with sheet of prepreg separating the copper

Layer. Outer layer are made with a foil of copper.

Stack is pinned between heavy metal plates creating a “book”

“Book” is put it a heated hydraulic press for about 2h

Prepare is available in different styles with varying amounts of resin and glass fibers.

This allow the manufacturer to control thickness between layers and thickness of the

overall PCB

Pcb shear

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DRILLING AND CLEANING

Each layer of the printed circuit board requires the ability of one layer to connect to another,

this is achieved through drilling small holes called "VIAS". These drilled holes require

precision placement and are most commonly done with the use of an automated drilling

machine. These machines are driven by computer programs and files called numerically

controlled drill or (NCD) files also referred to as excellent files. These files determine the

position and size of each file in the design.

Some files require very small vias to be drilled which results in heavy wear and tear of the

drill bit itself. Drilling through different substrates may require the drill bit to be made of

tungsten carbide and are costlier than other materials but required to provide a proper hole.

Controlled depth drilling can be used to drill just one layer of the circuit board rather than

drilling through all the layers. This can be accomplished by drilling the individual sheets or

layers of the PCB prior to lamination.

Blind Vias : Is when the holes connect a layer to the outside surface

Buried Vias : Is when the holes only connect interior layers and not to the outside

surface.

http://www.trianglecircuits.com/pcb-terms.html#via



http://www.trianglecircuits.com/pcb-terms.html







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The walls of each hole (for multi-layer boards) are copper plated to form plated-through holes

that connect the conductive layers of the printed circuit board.

Purpose : holes are drilled through PCB to interconnect layer (vias) allow the

insertion of PTH components

Drilling is performed with CNC equipment

Using drill files. Alternative method use punching or laser

Multiple panels can be drilled together

Drilling of complex boards can take several hours per load

Desmear – remove the melted resin smear

Panels are debarred /scrubbed after drilling

PCB substrate is not conductive. Therefore a non-electrolytic deposition method is

required

Process : electro less copper

DRILLING AND CLEANING BRUSH CLEANING MACHINE

http://www.trianglecircuits.com/pcb-terms.html#thole




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OUTER LAYER IMAGE

Most common process : print, pattern plate and etch

Coat copper foils with photo resist

Place photo tool and expose to light

Outer layer photo tools are positive image of the circuit. Circuit image is

developed away exposing the copper. PR remaining on the panel will act as plating

resist

Etching

SURFACE FINISH

Purpose : prevent copper oxidation

Most popular surface finish process :

SMOBC/HASL SMOBC = Solder-mask-over-bare-copper

HASL = Hot-air-solder-leveling

Purpose of solder mask : insulate those portions where no solder is required

HASL – Panels are dipped into molten solder (237^C). Exposed copper is coated

with solder. Masks areas remain solder-free. Panels are the cleaned in hot water.

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FINAL FABRICATION

Routing done through CNC machines

De-penalization

Most of the circuit is routed out of the panel, but tabs remains to hold the circuit in

place. This allow machine to populate boards at once. Afterwards, the circuit can be

broken out of the panel. Such panel are called “array”, “breakaway”.

Alternative de-penalization is to have the panel v-scored. It done through a thin

rotating scoring blade that will route across the top & bottom of the panel with

about 30% of the thickness. V-scoring allows more circuits per panel. (no spacing is

required for router bits)

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TESTING & INSPECTION

PCB inspection is an essential element in any electronics manufacturing process. The PCB

inspection enables faults to be detected as soon after the manufacture process as possible .

As such the PCB inspection process is an essential element of any PCB manufacturing

process.

AAOI - Automatic Optical Inspection, state of the art system capable of in depth

analysis of final build compatibility detecting a multitude of faults.

Functional Testing.

Automated optical inspection (AOI)

Inspection inner layer circuit before lamination

X-ray & Scanning laser system

Monitor registration accuracy and pinpoint defects after lamination

Final inspection (manual ,automated)

Manual-operator visually inspecting the boards via optics and making

judgments.

Automated-employs computer added image analysis for determining defects .

When pcb inspected and tested-evaluate the cost effectiveness of repairing the

board . Re paired/rework is not allowed in high reliability and military

application . Only for commercial application is allowed . Repaired must meet

the original design requirement , reliability and quality standards .

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There are 3 method of testing :

AUTOMATIC TEST EQUIPMENT

Any automated devices that use to quickly test like PCB , IC ,or any other

electronics component . ATE devices always controlled by computer . System

simple as digital multi-meter . All the operating , measurements is controlled

and analyses by computer . Example , flying probe tester PCB bed of nails .

Are used to test a wide range of electronics devices & system . ATE system

typically interface with handler , physically places the devices so that it can be

measured .

BOUNDARY SCANNING

Boundary scanning is a method for testing interconnections (wire line) on

printed circuit boards or sub blocks inside an integrated circuit. Test

interconnections and clusters of logic , memories without using physical test

probes .

BURN IN TEST EQUIPMENT

Burn in test equipment uses elevated voltages , temperatures and power

cycling to evaluate high power chips , boards or products . The burn in

process tests the quality of semiconductor devices before it is incorporated

into a finished devices . Burn in test equipment accelerates any potential

failures in substandard products , known as the infant mortality .Devices that

survive a burn-in period are usually free of early failures and other operational

problems

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There are two main uses for a PCB inspection system:

High light manufacturing defects: The obvious function of a PCB inspection system

is to highlight any defects so that they can be corrected before they are passed on to

the next stage in the production process. Finding faults as early as possible in the

production process is essential because fault finding and fixing costs rise by

approximately a factor of ten as each stage in the production process is passed.

Provide process feedback: An equally important function of a PCB inspection

system is to provide feedback into the manufacturing process. Using a PCB inspection

system on the output of the soldering process can enable any pattern faults to be seen

and the process corrected almost immediately to reduce or eliminate the occurrence of

a given problem.

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PCB DataPreparation

Laminatepreparation

inner layerimage

transfer

Lamination Drilling &Cleaning plate throughholes

Outer layerimage

transfer

SurfaceFinish

FinalFabrication

Testing &Inspection

MULTILAYER FLOW DIAGRAM

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b) Draw the building concepts of multilayer rigid Printed Circuit Board that consist of:

i) 16 LAYER BOARD

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ii) BURRIED VIA BETWEEN LAYER 2 to 7 and 6 to 12

BURRIED

VIA

2 to 7

BURRIED

VIA

6 to 12

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iii) Blind via between layer 4 to 10

BLIND

VIA

10 -16

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c) By choosing any circuits , design the circuit for single layer of printed circuit board

(PCB)

SCHEMATIC

This circuit consists of 3 IC, the Ic that I used is, IC – 555 and 2 IC 4026. This

circuit using less than 20 component. This circuits count using 2 7-segments.

LAYOUT USING PROTEUS

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PCB WILL BE LIMITED TO:

SINGLE LAYER

This is a single layer printed circuit board

ROUND HOLES

Round - Round holes are the default hole shapes and can define their hole sizes.

ROUND HOLE

So this is a normal shape of pcb

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FABRICATION PROCESS

FIND THE SUITABLE CIRCUIT

circuit can be found everywhere, for example in a hobby kit or on the internet, but make sure

it has a 3 ic to complete the specification given. And not using ball grid array IC.

THEN TRY TO MAKE A CIRCUIT USING SOFTWARE MULTISIM OR PCB

DESIGNER

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DRAW THE CIRCUIT USING MULTISIM USING SOFTWARE PCB DESIGNER

PRINTED THE CIRCUIT LAYOUT

This is machine Photostat that will print the layout

The layout will be print using

the machine Photostat

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They are so cheap its certainly worth a try, and with this as many different media types as

will people find, but don’t expect the same quality can get from lasers . The main problem

will be getting an opaque enough back. It may also be worth trying an inkjet print onto paper

which can be photocopied onto tracing paper with a good quality copier. This process above

show , for the first step draw the schematics , it is depend to make a circuit using a multisim

or using pcb designer software , Both of this is a software that always people use and easy to

find that .

THEN CHOOSE A BOARD TYPE AND DEMENSION

USING SINGLE LAYER PCB

-Easily the best all round solution. Very affordable, fast

and good quality. The printer used must have at least

600dpi resolution for all but the simplest PCBs, as you will

usually be working in multiples of 0.025 (40 tracks per

inch). 300dpi does not divide into 40; 600DPI does, so

people can get consistent spacing and line width. It is very

important that the printer produces a good solid black with

no pinholes

LASER PRINTER

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-A functional PCB is not a finished products. It will always require connections the

outside world to get power, exchange information, or display results. It will need to fit

into a case or slide into a rack to perform its function.

PLACE THE LAYOUT TO THE PCB BOARD

This is a circuit that has been made in multisim and was later transferred to ultiboard then be

like this. But if wish for simple connection might try to use other software such as software

pcb designer, design can be made in accordance with their respective tastes. And below is a

picture using software pcb layout designer to create. But before that should be used

transparently to stick it in the pcb board layout.

IRON THE TRANSPARENT CIRCUIT ON THE PCB BOARD

No need to iron that

is too long for fear

the circuit will be

expanded.

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This is an increase in the need to know the layout of all the iron. Layout made would have

been transferred to the pcb with on its own. If you do not iron it will not be the desired

circuit, when the iron layout onto the whole surface of the pcb should iron this board because

they want to stick all of the layout that is transparent to the board. Do not need a long time

when iron is sufficient if it knew it was stuck, if too long then the permanent layout of

flowers, and this will be difficult to go to the next process. Photos above are part of the

sample is done to complete the circuit.

ETCHING PROCESS

This is an etching process to be aware, this process will be made to the circuit 12 led sign

board lights . If you want a fast etching may use means such as manual and if you want to

update and want to just use energy-saving auto ways of using etching machines. Etching is a

process that is very simple and everyone can do it. Small board will make it easier again to

etching when using a large board may cause a waste of time and wastage in the use of

etching. Photo above shows examples of etching processes. This machine etching do the

package etching then clean the board.

-Etching is probably the easiest and most cost effective .It

is the process of chemically removing copper from a

plated board you must put a mask or resist on the portions

of the copper that you want remain after the etch these

portions that remain on the board are traces that carry

electrical current between devices .

If etching is added to

boiling water it will be

easier for cooper off.Clean the pcb

using water

Etching process

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DRILL THE PCB BOARD PROCESS

This is a mild increase in the process to complete each circuit, the following process is

concerned with the process of drilling pcb board it really looks easy, but if not done

so will not prepare the required by the circuit. Each pad is round or square pads,

which have previously have designed the layout using the software updates should be

at the drill with the drill because the process is still there the following process is

necessary soldering each component. Drilling is very important it is intended to

include all components of the foot. When drilling pcb board should be cautious and

careful because like neatness in making things

PLACE AND SOLDER THE COMPONENT ON THE PCB BOARD

This is a process in all components has been compiled and placed on the pcb and the

most important thing is process soldering all component at the pcb, the process

requires a soldering iron and tin components then be attached to the layout.

TEST FUNCTIONALITY CIRCUIT

Test counter circuit after complete soldering iron the all component at layout.

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COMPLETE PCB CIRCUIT WITH WIRING

Describe the different in designing and simulation between single and double layer of

PCB . Give your comment .

SINGLE SIDED DOUBLE SIDED

Wiring is available only 1 slide Wiring is available on both side

Difficult to design layout if circuit is

complicated

Easy to design layout if circuit is complicated

Component in the layout cannot arrange

in sequences.

Component can arrange in sequences.

When etching it need more time. Save time when etching.

Easy to transfer the layout to the PCB

board.

Difficult to transfer the layout to the PCB

board.

Single sided board are cheaper. Double sided board are more expensive .

Put all the circuits

in the casing after

the circuit has

function.

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Single layer

Single sided Printed circuit board has copper tracks/circuit only on one side of the board and

are often referred as Print and etch board . These are without plated through holes and can

have component on one sided as well as on both sided (in case of SMD) . Single side PCB are

most commonly used in consumer electronics

DOUBLE LAYER

Double layer Printed circuit board has copper tracks/circuit on both side of a PCB and may or

may not be connected . Both sides can be connected together by depositing copper inside the

holes (plated through holes ) . In terms of assembling a double sided PCB can have

components on one side as well as on both sides . Double sided PCB are commonly used in

industrial .

COMMENT

When designing single layer and double layer , get learn more about this process , also get

knowledge about Printed Circuit Board (PCB) . When designing single layer it is very easy

to transfer the layout to the PCB board because only one layer use to transfer. But sometimes

when using double layer , it seem difficult to transfer the layout to the PCB board . The

conclusion that can make is , both of the single layer and double layer have an advantage and

disadvantage when using . So from that try to use the design circuit .

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TASK 4

DESIGN CONSIDERATIONS

FABRICATION PROCESS

a) Provide the aluminum board and measure

Measure each part to be cut, this process is

necessary if the accuracy of every detail to get

right in the measure so that the results will look

good and not have a defect that occurs when

making the casing. Measured using tools such as

rulers .

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b) Then cut the aluminium board with follow the measurements

c) Drilling the aluminium

Next picture shows how to cut aluminium, the

aluminium after the measure is the process to cut

further Top, in college there was a large aluminium

tool and it is only used to cut the aluminium. How to

wear it is to be put aluminium the above place the

cutter and close aluminium and finally step foot in

the cutting of aluminium, then after that will be

Truncated.

Once bend the aluminium, then it is time to drill a

hole casing, it seeks to put the nail in the casing. Prior

to that mark holes in areas where it is due to be in the

drill because it is feared there will be miss-drill and a

defect in your aluminium casing. Use a large drill

point if you want a big hole and use a small drill

point to drill small holes for the screws.

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d) Bend the aluminium

e) The aluminium board after bend

e) The next process is leveling the surface of the aluminum in drill.

Aluminium has been cut should be bent to create

a casing in the shape of a rectangle, using the

stick method is only by raising the rod bend tool

that has been provided. Lift the metal bars on the

Bend will be down to create the form.

This next picture shows how the appearance

of the aluminium after it is bent according to

their tastes. When bending aluminium to be

careful it because aluminium is sharp and

can make the hand would be injured if

exposed to the fragments.

Smooth out any part of the casing in bend. it is

also to smooth casing back.

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iv) FINISHING PROCESS

a) Spray the casing

b) Into the circuit in the casing

Front View Side View

Back View

This is a finishing process where the casing

has been spray to look more attractive. It

can also be covered from any scratches

After try the functionality of circuit , try to into the

circuit in the casing . making it the casing should be

neat to see the looks beautiful on the outside.

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b) What skills would you need in the development aluminium casing and what resources

would you look for in the formation of a project team.

In the group must have the tasks distributed to make a project:

Designing

This is where we should make a sketch of the casing before cutting. This facilitates

all the work done, and will look more neat and orderly.

Technician

This part where we assemble component and solder component on PCB.

This part very important because to make sure the project can function

properly.

Manufacture

After settle everything, this part we call finishing project, where we put the

circuit on the casing properly.

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c) Explain the main purposes for producing models representatives of the final form of

a product.

Process mapping approaches such as value – stream mapping have several

disadvantages over good system modelling. First, by definition, they map processes or

process flows, and not systems. Second, they assume that there is only one point of

contact with the customers- the final or services that is produced or delivered

information flows for a single product (of group of product) and as such it maps only

the flow of process interactions for the product out of the finals customer. In reality,

organizations do not have a single point of contact with customers, customers make

many different types of request product and services upon an organizations and the

demand for the final product is only one of many such requests. Accordingly, achieving

true excellence in performance means achieving excellence in customer satisfactions

across the full spectrum of these interactions and bot just in the final product or

services provided to customers.

For example, beyond for the final product or services customers may require an

organizations to satisfy a range of diverse requests and demands, including those for

quotes and pricing, warranty support and services call, sales order processing and

acknowledgement, supplier purchases, product information, product and process

design, payment processing, delivery logistics, etc. A viable system model takes into

account all of these interactions, defines the needed core and support processes along

with their sequence and interactions and determines the needs to be filled and the

outputs to be provided. Most important, the risks associated with achieving customer

satisfaction through “ fitness for purpose” in each of the customer interactions must be

identified, assessed and managed.

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CONCLUSION

The conclusion that can make from this assignment is can learn more about the electronics

component design parameters & PRINTED CIRCUIT BOARD. Beside that also get many

knowledge about many process in printed circuit board. Printed circuit board also referred as

printed wiring board @ etched wiring board. it is use to mechanically support & electrically

connect electronics components using pathway or traces . Also can be divided into 2 types

rigid and flexible.

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